The United States feared Vladimir Putin would lose control of his nuclear arsenal in a coup attempt in Russia by Yevgeny Prigozhin.
Intelligence officers had gathered information that Chief Wagner and his mercenaries were planning a coup 10 days ago, but were unsure of the exact timing.
“Even so, there were enough signals to be able to tell[US]leaders that something was wrong,” the Washington Post quoted a US intelligence official as saying.
Sources said the US government chose not to intervene to avoid escalating a dangerous situation that threatened civil war.
Mr Putin controls Russian nuclear missiles and is followed by a security guard who carries a “nuclear briefcase” with the triggers.
“You want to know who controls nuclear weapons because you’re worried about terrorists or bad guys like Kadyrov going after them,” said Daniel Hoffman, a former senior CIA officer.
Ramzan Kadyrov is the leader of Chechnya’s warlords.
One of the triggers for Saturday’s coup attempt was a June 10 Kremlin order that mercenaries must sign a contract to fight under the regular Russian army.
US officials said they have been monitoring a Wagner coup attempt ever since.
“We have all seen Mr. Prigozhin publicly criticize, and even threaten, the Russian military on many occasions,” a White House official was quoted by US media as saying.
Mr. Prigozhin and his fighters said their rebellion only targeted senior Russian military commanders.
They captured Rostov in southern Russia on Saturday morning, then headed for Moscow before halting and disbanding.
According to reports, Alexander Lukashenko, President of Belarus, brokered a deal allowing Mr Prigozhin to call off his coup.
He agreed to go into exile in Belarus on the condition that his Wagnerian mercenaries remain independent of the Ministry of Defence.
The Kremlin appears to have ensured that Sergei Shoigu and Valery Gerasimov retain their positions as defense minister and Russia’s top military commander.
“If Prigozhin intended to drive a wedge between the Russian armed forces command and the Kremlin, he failed,” a Western official told The Washington Post.
Meanwhile, the United States has postponed a new sanctions package against the Wagner Group due on Tuesday, according to the Wall Street Journal, for fear of strengthening Putin’s hand.
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