In late January, with his mercenary forces dying by the thousands in a prolonged fight for the ruined city of Bakhmut, Wagner Group owner Yevgeney Prigozhin made Ukraine an extraordinary offer.

Prigozhin said that if Ukraine’s commanders withdrew their soldiers from the area around Bakhmut, he would give Kyiv information on Russian troop positions, which Ukraine could use to attack them.

The mercenary forces chief conveyed his proposal to his contacts in Ukraine’s military intelligence directorate, with whom he has maintained secret communications during the course of the war, according to previously unreported U.S. intelligence documents leaked on the group-chat platform Discord.

Wagner Group owner Yevgeney Prigozhin offered to give Ukraine information on Russian troop positions in exchange for Kyiv pulling back troops fighting Wagner’s mercenary forces, according to leaked U.S. intelligence documents. Associated Press, file

Prigozhin has publicly feuded with Russian military commanders, who he furiously claims have failed to equip and resupply his forces, which have provided vital support to Moscow’s war effort. But he is also an ally of Russian President Vladimir Putin, who might well regard Prigozhin’s offer to trade the lives of Wagner fighters for Russian soldiers as a treasonous betrayal.

The leaked document does not make clear which Russian troop positions Prigozhin offered to disclose.

Two Ukrainian officials confirmed that Prigozhin has spoken several times to the Ukrainian intelligence directorate, known as HUR. One official said Prigozhin extended the offer regarding Bakhmut more than once, but that Kyiv rejected it because officials don’t trust Prigozhin and thought his proposals could have been disingenuous.

A U.S. official also cautioned that there are similar doubts in Washington about Prigozhin’s intentions. The Ukrainian and U.S. officials spoke on the condition of anonymity to discuss sensitive information.

In an interview with The Washington Post this month, Ukrainian President Volodymyr Zelensky would not confirm the contacts with Prigozhin.

“This is a matter of [military] intelligence,” he said.

The Ukrainian leader also objected to airing classified information publicly and said he believed that the leaks had benefited Russia.

But there is no debating Prigozhin’s bitter frustration with the grinding fight in Bakhmut. He has complained, publicly and privately, that the Russian Defense Ministry has not given his fighters the ammunition and other resources they need to succeed. Bakhmut, in eastern Ukraine, has seen some of the bloodiest fighting of the war. Over the past few months, in a grinding back and forth measured by city blocks, Ukrainian and Russian forces have taken steep casualties.

Prigozhin, who had promised to take control of the city by May 9, in time for Russia’s Victory Day celebrations, has recently threatened publicly to pull his forces out of the fight.

Other leaked documents reveal Russian Defense Ministry officials privately wondering how to respond to Prigozhin’s criticism of the military’s performance and his demands for more resources, which they apparently conceded were not illegitimate grievances. The documents also speak to a power struggle between Prigozhin and top officials, including Russian Defense Minister Sergei Shoigu.

Against that tense backdrop, Prigozhin has carried on a secret relationship with Ukrainian intelligence that, in addition to phone calls, includes in-person meetings with HUR officers in an unspecified country in Africa, one document states. Wagner forces provide security to several governments on that continent.

The leaked U.S. intelligence shows Prigozhin bemoaning the heavy toll that fighting has taken on his own forces and urging Ukraine to strike harder against Russian troops.

According to one document, Prigozhin told a Ukrainian intelligence officer that the Russian military was struggling with ammunition supplies. He advised Ukrainian forces to push forward with an assault on the border of Crimea, which Russia has illegally annexed, while Russian troop morale was low. The report also referred to other intelligence noting that Prigozhin was aware of plummeting morale among Wagner forces and that some of his fighters had balked at orders to deploy in the Bakhmut area under heavy fire, for fear of suffering more casualties.

The Kremlin did not respond to a request for comment about Prigozhin’s communications with Ukraine.

In wartime, it is not unusual for opposing parties to maintain some form of communication. And the documents don’t reveal Prigozhin’s intention in talking to his erstwhile foes in Ukraine. One Ukrainian official characterized the contacts in the spirit of “keeping your friends close and your enemies closer.”

The documents also suggest that Kyiv suspects, or may know, that the Kremlin is aware of Prigozhin’s communications with Ukrainian intelligence, if not his secret negotiations over Bakhmut.

One document, based on “sigint” – or intercepted communications – says that Ukraine’s military intelligence chief, Kyrylo Budanov, “expected the Russians to use details of Prigozhin’s secret talks with the HUR and his meetings with their officers in Africa to make him appear to be a Ukrainian agent.” It doesn’t specify whether Budanov suspects Moscow may already know that Prigozhin is talking to HUR officers.

When informed that U.S. intelligence documents revealed Prigozhin’s communications with Ukrainian intelligence, the mercenary commander appeared to make light of the situation. “Yes of course I can confirm this information, we have nothing to hide from the foreign special services. Budanov and I are still in Africa,” Prigozhin wrote on Sunday via his Telegram channel.

Prigozhin didn’t immediately respond to a question about his offer to disclose Russian troop positions in exchange for a Ukrainian pullback in Bakhmut.

The Washington Post’s Mary Ilyushina in Riga, Latvia, contributed to this report.