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On Sunday, The New York Times reported that President Trump's personal legal counsel, Michael Cohen, met last month with a colorful Russian-American former Trump business associate, Felix Sater, and a pro-Moscow Ukrainian lawmaker, then delivered a sealed envelope from them to Michael Flynn, Trump's then-national security adviser, with a "peace plan" for Ukraine. The peace deal, proposed by Ukrainian lawmaker Andrii Artemenko, would lead to formalizing Russia's occupation of Crimea as a lease and lifting U.S. sanctions against Russia.

Cohen and Sater confirmed the meeting and the envelope delivery. Then on Monday, Cohen backpedaled, telling The Washington Post and NBC News that "the brief meeting took place," but "emphatically" denying "discussing this topic or delivering any documents to the White House and/or General Flynn." He agreed to meet with Sater for coffee, he added, because he's "known Felix for years," and didn't know Sater's friend "would be a guy who wants to run for president of Ukraine." The Times stood by its story, telling The Washington Post that Cohen said "in no uncertain terms that he delivered the Ukraine proposal to Michael Flynn's office at the White House."

The back-channel diplomacy effort is not illegal, though it is unusual and maybe inconvenient amid federal investigations into Trump's business and political ties to Moscow. The reappearance of Sater is interesting, in any case, not least because he has a colorful history that includes arrests for stabbing a man in the face with a broken glass in a bar fight and for a Mafia-linked stock-fixing scheme, and avoiding jail by working for the CIA and FBI.

Sater's long business history with Trump includes working on several Trump-licensed projects, including the Trump SoHo building and — a decade ago and again in 2015 — a proposal to build a Trump Tower in Moscow. Sater's name has popped up a couple of times in the campaign, but despite evidence of their close ties, Trump has sworn in depositions that he wouldn't even recognize Sater's face, as shown in this December 2015 report from ABC News.

The peace proposal did not meet with a positive response in either Kiev or Moscow; Kremlin spokesman Dmitry Peskov called the plan "absurd," and Ukrainian Ambassador Valeriy Chaly said that Artemenko "is not entitled to present any alternative peace plans on behalf of Ukraine to any foreign government."