Using the Kremlin’s interpreter was “a very bad idea” that put Witkoff “at a real disadvantage,” Michael McFaul, a former U.S. ambassador to Russia, told NBC News.

Donald Trump’s special envoy broke with long-standing protocol by not employing his own interpreter during three high-level meetings with Russia’s Vladimir Putin, opting instead to rely on translators from the Kremlin, a U.S. official and two Western officials with knowledge of the talks told NBC News.

Steve Witkoff, who has been tasked with negotiating an end to the war in Ukraine, met with Putin in Moscow for several hours on Feb. 11, on March 13, and in St. Petersburg on April 11, and “used their translators,” one of the Western officials said. “If they speak to each other in Russian, he doesn’t know what they are saying,” the official added, referring to Putin and the interpreters.

Witkoff, a former real estate mogul and cryptocurrency trader, does not speak Russian. By using Kremlin interpreters, he ran the risk that some of the nuance in Putin’s messages was missed and he would not have been able to independently verify what was being said to him, two former American ambassadors said.