NAIROBI, Kenya — Fueled by weapons, gold and social media, the rivalry between Russia and the West in Africa is quickly escalating. The newest flashpoint is Chad, a sprawling desert nation on the crossroads of the continent, now a plum goal for Russia’s increasing effort.

America just lately warned Chad’s president that Russian mercenaries had been plotting to kill him and three senior aides and that Moscow was backing Chadian rebels massing within the neighboring Central African Republic. On the identical time, Moscow is courting sympathizers inside Chad’s ruling elite, together with cupboard ministers and a half brother of the president.

The choice by the U.S. authorities to share delicate intelligence with the top of an African state — a disclosure it then leaked — reveals a method during which the Biden administration is transferring extra assertively in Africa and utilizing new techniques to stymie Russian good points on the continent.

The U.S. is taking a web page from its playbook in Ukraine, the place it has used categorized data to reveal Russian navy plans and pre-empt what it says are Chinese language plans to produce Russia with new weapons.

In Africa, the extra forceful American method goals partly to shore up the crumbling place of France, which lately has ceded floor to Russia in former colonies like Mali and the Central African Republic. Now the Russians want to topple extra French dominoes in central and western Africa, and the USA is responding.

A U.S. official, who like others interviewed for this text spoke on the situation of anonymity to debate issues of nationwide safety, mentioned the assassination plot in Chad represented “a brand new chapter” in efforts by Wagner, the Kremlin-backed personal navy drive, to advance Russian pursuits in Africa.

Till now, Yevgeny Prigozhin, who leads Wagner, has established footholds in susceptible African nations by sending his fighters to prop up tottering authoritarian rulers, normally in trade for fee, or licenses to mine diamonds or gold.

The plot in Chad suggests that he’s now able to topple leaders who stand in his means. That change has prompted the USA to undertake extra forward-leaning measures, like these utilized in Ukraine, which might be supposed “to gradual, to curb, constrain and reverse” Mr. Prigozhin’s enlargement in Africa, the official mentioned.

“The place Wagner has been current, dangerous issues have inevitably adopted,” Secretary of State Antony J. Blinken mentioned on a go to to Niger on Thursday.

The go to, throughout which Mr. Blinken pledged $150 million in assist to the Sahel area, was the fourth to Africa by a senior U.S. determine this yr. Treasury Secretary Janet L. Yellen; Linda Thomas-Greenfield, the ambassador to the United Nations, and the primary woman, Jill Biden, preceded him. Vice President Kamala Harris will start a visit to Ghana, Tanzania and Zambia this month, and President Biden has promised to go to Africa later this yr.   

To many in Africa and past, the heightening great-power rivalry smacks of the Chilly Conflict, when the USA and the Soviet Union backed rival African leaders, together with dictators. It’s a comparability the Biden administration desperately needs to keep away from as a result of its technique in Africa, introduced by Mr. Blinken to fanfare in South Africa final yr, presents African nations as valued companions, not pawns in a world rivalry.

For his or her half, African leaders have made it clear that they don’t need to be compelled to decide on sides.

“Africa has suffered sufficient from the burden of historical past,” Macky Sall, the African Union chairman, instructed the U.N. Basic Meeting in September. “It doesn’t need to be the breeding floor of a brand new Chilly Conflict.”

Russian ties to Africa stretch again to the Soviet period, when Moscow backed sympathetic governments and independence actions, and have endured lately as Russia grew to become the continent’s largest arms provider.

However its newest drive for affect began in earnest about 5 years in the past, when Mr. Prigozhin’s Wagner mercenaries — many Russian but additionally Syrian, Serbian and Lebanese — started to appear in among the continent’s most turbulent corners.

In response to questions, Mr. Prigozhin mentioned in an announcement, “We have now nothing to do with both the Chadian rebels or Mr. Hemeti,” a nickname for the deputy chief of Sudan, Gen. Mohamed Hamdan, who additionally wields affect in Chad.

The Russian effort spans the continent however has had the best influence within the Sahel, the semiarid area bordering the Sahara. Wagner fighters are battling Islamist rebels in Mali, are bodyguards to the Central African Republic’s president and mine gold in a number of nations, together with Sudan. Social media campaigns search to burnish the picture of President Vladimir V. Putin or to faucet into wellsprings of anti-French resentment.

The arrival of Russian mercenaries prompted the French navy to withdraw from a number of nations. In November, France formally ended Operation Barkhane, its eight-year navy drive in opposition to Islamist insurgents within the Sahel that, at its peak, included troops from 5 African nations. One in all them, Mali, is now firmly within the Russian orbit.

The warfare in Ukraine didn’t blunt Russia’s push into Africa. American officers say that Wagner has maintained between 3,500 and 4,500 personnel on the continent, even because the group additionally throws troops and jail conscripts into the “meat grinder” of Ukraine’s longest, most brutal battles.

As an alternative of retracting, Russia is probing for brand spanking new toeholds in Africa.

On a latest go to to Mali, Russia’s overseas minister, Sergei Lavrov, talked about Guinea, Burkina Faso and Chad in a speech as nations the place Russia hoped to make use of counterterrorism to get its foot within the door. U.S. officers have detected indicators of recent Wagner hyperlinks in Eritrea, suggesting a want for a coast-to-coast sphere of affect from the Atlantic Ocean to the Pink Sea.

Mr. Lavrov has visited seven African nations this yr, looking for to capitalize on ambivalence over the warfare in Ukraine and overtly acknowledging Russia’s hyperlink with Wagner. Whereas 30 African nations condemned Russian aggression in a latest vote on the United Nations, 22 selected to not.

Russia has additionally obtained a robust associate in Basic Hamdan of Sudan, whose paramilitary forces have obtained weapons and coaching from Wagner, and who travels extensively throughout the area. Final week, he flew to Eritrea, one among a handful of nations that constantly votes in favor of Russia on the United Nations.

Specialists warning in opposition to overestimating the influence of Russia’s African forays. The nations the place Moscow operates are among the many world’s poorest, and on the bottom, its efforts typically seem scattershot, poorly resourced and motivated by a want to poke the West within the eye. In the end, Russia is unlikely to ship on the grand safety guarantees it has made to African nations, mentioned Michelle Gavin, an Africa skilled on the Council on Overseas Relations.

However within the quick time period, its actions are proving extremely disruptive, and Western powers have struggled to discover a response.

Within the West African nation of Burkina Faso, quickly after Capt. Ibrahim Traoré, a younger military officer, seized energy in a coup final fall, Victoria Nuland, a senior State Division official, confirmed as much as strongly urge Mr. Traoré to not flip to Wagner for assist, a senior State Division official mentioned.

In January, the final French troops left Burkina Faso, underneath orders from Captain Traoré, prompting hypothesis that they might get replaced by Russians.

But it surely was the assassination plot in Chad, first reported by The Wall Avenue Journal, that spurred American efforts to a brand new degree.

Bigger by space than Britain, France and Germany mixed, Chad has been a key French ally for many years, utilized by the French navy for coaching and as a hub of operations. Within the Nineteen Eighties, the C.I.A. supported its brutal chief, Hissène Habré, who was later convicted as a warfare legal.

Chad’s present chief, Mahamat Idriss Déby, got here to energy in 2021 after his father, Chad’s autocratic chief of three many years, was killed in battle with rebels. Mr. Déby has stayed near France, however the alliance has been frayed by a brutal crackdown on democracy protesters in October that left 128 folks lifeless, in line with Chad’s nationwide human rights physique.

Now, some members of Mr. Déby’s inside circle look like tilting towards Russia.

A senior Chadian official who spoke on situation of anonymity mentioned that Mr. Déby’s half brother, Seid, a former head of Chad’s state vitality firm, visited Moscow thrice prior to now yr, assembly not less than as soon as with Mr. Prigozhin. On his Fb profile, Seid Déby is pictured standing exterior the Kremlin.

In January, Russia denied accusations that Wagner was looking for to topple the president and introduced that Mr. Déby deliberate to attend the second Russia-Africa summit in July, hosted by Mr. Putin.

About 4 weeks later, U.S. officers offered Mr. Déby with declassified proof of Wagner’s plans to assassinate him, the Chadian official mentioned. Additionally on the hit checklist had been Mr. Déby’s chief of workers, a minister of state and the chief of the presidential guard, he added.

Seid Déby and the spokesman for Chad’s president didn’t reply to requests for remark.

Washington has continued to make use of its standard instruments in opposition to Mr. Prigozhin’s community in Africa, imposing new sanctions in January that focus on his enterprise ventures and associates in a number of nations. The French, in the meantime, have begun to acknowledge that deep resentment towards them of their former colonies opened the door to Russian intervention.

On a latest tour of 4 African nations, President Emmanuel Macron acknowledged the rising wave of anti-French sentiment and promised a brand new period of partnership.

For some Africans, the present of humility has come too late. “The folks of Chad are not looking for the French,” mentioned Hallowak Haoua, 29, a avenue vendor within the Chadian capital, Ndjamena. “A minimum of the Russians need to assist us. With the French, it’s simply for their very own pursuits.”

Others fear {that a} return to Chilly Conflict-style confrontation might doom their democratic aspirations. America mustn’t cozy as much as authoritarians like President Déby of Chad to forestall him from tumbling into the Russian orbit, mentioned  Succès Masra, the principle opposition chief.

“It might be an enormous mistake for President Biden to facet with Déby,” mentioned Mr. Masra, talking by cellphone from the USA, the place he fled after the bloodbath of protesters in October. He added, “In the long term, the easiest way for the USA to guard its pursuits in Chad is to guess on democracy.”

Eric Schmitt contributed reporting from Washington, and Mahamat Adamou from Ndjamena, Chad.