That's according to a court filing from defense lawyers Tuesday responding to allegations that Manafort has repeatedly lied to special counsel Robert Mueller's team of investigators.
The details accidentally released Tuesday are the closest public assertion yet in the Mueller cases of coordination between a Trump campaign official and the Russian government, as Kilimnik is believed to be linked to Russian military intelligence.
The polling data was shared in the spring of 2016, the Times reported, and while most of the polling in question was publicly available, some of the data shared was assembled by a private firm on behalf of the Trump campaign.
The peace plan refers to the conflict that erupted in Ukraine in 2014, after President Viktor Yanukovych fled the country amid mass protests. At around the same time, Russian government operatives were allegedly hacking Democratic computers to help Trump and orchestrating a social media propaganda scheme to sway voters against Trump's electoral opponents. But an unredacted section notes some events occurred while Manafort was managing President Trump's 2016 campaign.
Manafort's filing also acknowledges he met with Kilimnik in Madrid. Trump has said there was no collusion between his campaign and Moscow. At a hearing in December, the federal judge overseeing Manafort's case in Washington D.C. asked the government to provide some "underlying evidence" to support the scant details they've offered about the content of his alleged lies. Manafort has not been charged with crimes related to his work for Trump.
Manafort, 69, has been in jail since June 15, when U.S. District Judge Amy Berman Jackson ordered him locked up after Mueller accused him and Kilimnik of witness tampering.
Manafort's lawyers said in the filing that any discrepancies in his cooperation could be due to the hours and length of his interviews.
Mr Kilimnik was considered Manafort's right-hand man in Ukraine and has been accused by the special counsel of conspiring to obstruct justice.
The errant admissions in Manafort's court filing also acknowledge that a person wanted to use his name when meeting President Donald Trump.
The revelations came to light via a faulty redaction.
What does the filing say?
Mueller's team had previously said Manafort lied multiple times, including about his contacts with Trump administration officials.
Manafort's lawyers did not respond to a request for comment on the matter.
Federal prosecutors convinced a jury in August 2018 to convict Manafort on eight of 18 bank and tax fraud charges in a trial in NY.
Manafort is scheduled to be sentenced on February 8 in Virginia and on March 5 in Washington. If he is found to have breached the deal, he would lose any sentencing credits for acceptance of responsibility, prosecutors said. Manafort's attorney disputes the allegation saying he "provided complete and truthful information to the best of his ability".
Judge Amy Berman Jackson has ordered the government to provide a detailed factual basis about Manafort's lies, which is due January 14.
That hearing is now scheduled for later this month.
But Mueller's office said Manafort had lied about at least five subjects, including his interactions with Kilimnik. Instead, they claim that Manafort's memory was affected by early morning risings, long days of questioning, and health issues that include gout, depression, and anxiety.