Senior congressional leaders were briefed about the ongoing situation in Russia, according to a congressional aide.

U.S. intelligence officials told the so-called "Gang of Eight" -- the top Republicans and Democrats currently in congressional leadership-- in recent days about potentially concerning movements of Wagner Group forces and equipment build-ups near Russia. However, it was unclear to U.S. intelligence what was going to happen and when.

-ABC News' Trish Turner

A senior U.S. official says it is a mystery as to why Yevgeny Prigozhin stopped his march to Moscow given that he was seemingly in a dominant position.

The official said he was greeted as a hero in Rostov-on-Don. However, the senior official told ABC News that Prigozhin is in an "emotional state," and perhaps did it because he thought this would destroy Russia, or because he glimpsed his own end. It is impossible to tell whether Prigozhin thinks Russian President Vladimir Putin will actually honor their deal which included allowing Wagner group soldiers to be folded into the Russian military.

The official said that Belarus President Alexander Lukashenko was very effective, telling Prigozhin and Putin that this was all a misunderstanding and that they are both patriots and aligned for the same goals.

Putin is said to be completely shocked by how fast Wagner Group moved through Russia. For now, he is just trying to secure his position. He does not want to be seen negotiating over his defense minister, but the official says the U.S. believes concessions were made over Sergei Shoigu's future as well as others.

-ABC News' Martha Raddatz

Secretary of State Antony Blinken spoke Saturday with Turkish Foreign Minister Hakan Fidan to discuss the ongoing situation in Russia.

"Secretary Blinken reiterated that U.S. support for Ukraine will not change. The United States will stay in close coordination with Allies and partners as the situation develops," spokesperson Matthew Miller said.

Blinken also spoke with Ukrainian Foreign Minister Dmytro Kuleba on Saturday to discuss the situation in Russia, Miller said. Blinken reiterated that support by the U.S. for Ukraine will not change.

The U.S. will stay in close coordination with Ukraine as the situation develops.

-ABC News Shannon K. Crawford

Yevgeny Prigozhin will go to Belarus to ease tensions and the fighters of PMC Wagner Group who took part in the so-called "campaign" against Moscow will not be prosecuted, the Kremlin said Saturday evening.

The rest will be able to sign a contract with the Ministry of Defense, the President of the Russian Federation Dmitry Peskov told reporters.

"In the end, we managed to resolve this situation without further losses, without raising the level of tension," Peskov said.

"An agreement was reached that PMC Wagner would return to their camps," he added.

Gen. Mark Milley, the U.S. military's top general, told reporters Friday that it's likely too early to tell the impact of the Wagner Group mutiny on Russian President Vladimir Putin.

"We want to know the answer to that question," Milley said when asked at the National Press Club if Yevgeny Prigozhin's mutiny had left Putin weakened. "I don't think we have evidence, conclusive evidence, either way, yet too early to tell."

Milley acknowledged that Ukraine's counteroffensive is making steady progress, but moving slowly -- something he said was not surprising given how tough of a fight it is.

"At the end of the day, Ukrainian soldiers are assaulting through minefields and in the trenches, and this is literally a fight for their life. So yes, sure, it goes a little slow, but that is part of the nature of war," Milley said.

He also noted that the U.S. is considering sending cluster munitions to Ukraine, though no decision has been made.

-ABC News' Luis Martinez