According to former Radical Party member of parliament Andrii Artemenko, who finished testifying in the Mueller probe last week, Batkivschyna Party leader Yulia Tymoshenko knew in advance about a “peace plan” that Artemenko delivered to the White House in January 2017.

“[Yulia Tymoshenko] had been informed about my peace initiative because I discussed with her, my colleague, the possibility of promoting the peace plan,” Artemenko told the Kyiv Post in a telephone interview from the United States. “This was a couple of conversations where we discussed how we can work together against corruption of [President Petro] Poroshenko and prepare for the future,” the Kyiv Post wrote.

Natasha Lysova, a Batkivschyna spokeswoman, declined to directly confirm or deny Artemenko’s statement, instead stating that “Tymoshenko has consistently fought against corruption. It’s one of her top priorities and demand of Ukrainian people.”

“But Artemenko’s quote isn’t true and sounds like nonsense,” Lysova added.

Artemenko completed testimony on June 11 before a federal grand jury in Mueller’s investigation into Russian meddling in the 2016 U.S. Presidential Election. The activities of Michael Cohen, an attorney for President Donald Trump, have caught the investigation’s attention amid allegations of influence peddling and Russian meddling.

He added that he was asked about “the meeting with (personal lawyer of U.S. President Donald Trump) Michael Cohen and (Trump business associate) Felix Sater in January 2017.”

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Artemenko was stripped of his position in parliament and his citizenship in May 2017, months after he proposed a so-called “peace plan” destined for the desk of then-U.S. National Security Adviser Michael Flynn. At the time of the plan’s release, Tymoshenko, now a frontrunner in the 2019 presidential elections, was travelling to the U.S. for brief, ambush-style meetings with President Trump, the Kyiv Post recalls.

Under Artemenko’s plan, Ukraine would have “leased” Crimea to Russia for 100 years in exchange for Russia’s withdrawal from Donbas and a change in government in Kyiv.

He added that he had given over hundreds of documents, emails, and text messages to federal prosecutors.

Artemenko says he still has sky-high domestic political ambitions, at one point catching himself after saying that he wants to run for president in 2019.

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He adds that he appealed to the European Court of Human Rights to have his citizenship restored, hoping for a positive ruling by the end of the year.

“I’m preparing for the 2019 parliamentary election,” he said, adding that he has a vision of Ukraine as an “independent, unblocked country.”

“We’re not going to be a member of the EU, NATO, or of a Russian alliance,” he said. “We have to be an independent country.”