Kylymnyk told Christopher Miller in an exclusive interview to RFE/RL, Censor.NET reports.
In the February 22 interview, Kylymnyk denied any ties to Russian intelligence. But he said that he and Manafort spoke during the 2016 election "every couple months."
"I was briefing him on Ukraine," he said.
Manafort was fired by the Trump campaign in August after news reports documented payments to him from Yanukovych's pro-Russian political party.
Manafort told The Wall Street Journal last month, "I have never had any relationship with the Russian [government] or any Russian officials."
Kylymnyk also said that he had drafted a plan to bring peace to Ukraine in the nearly three-year-old conflict with Russia.
He referred to it as a "Mariupol plan," a reference to the southeastern port city that abuts the current line of conflict between government forces and Russia-backed separatist fighters.
It would bring Yanukovych back to Ukraine as a regional leader in the Donetsk and Luhansk provinces, where fighting has raged on and off for nearly three years, or possibly involve others such as the current separatist leaders there.
That plan, which Kylymnyk said Manafort was not involved with, would face almost certain opposition in Kyiv since it calls for Yanukovych returning to Ukraine from Russia, where he fled in February 2014.
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