Energy Secretary Rick Perry insisted Friday that his decision to leave Donald Trump’s cabinet is not tied to his dealings with Ukraine, as a House impeachment inquiry scrutinizes his role in an administration decision to withhold aid amid pressure to investigate the president’s political foes.

“It has absolutely nothing to do with Ukraine,” Perry said in a Fox News Channel interview, one day after handing Trump his resignation letter and about six months after the president said he first learned of his energy secretary’s plan to leave.

Perry said his work with Ukraine was focused on ensuring the country wasn’t held “hostage” by Russian gas -- an effort he said has been ongoing for more than two years, even when former Ukraine President Petro Poroshenko was in charge.

Trump has come under fire for a July 25 phone call in which he told Ukraine President Volodymyr Zelenskiy he wanted him “to do us a favor,” before asking him “to find out what happened with this whole situation with Ukraine” as it related to the 2016 election and citing “a lot of talk about Biden’s son” having “stopped” a prosecution in Ukraine.

Perry said Friday that he encouraged Trump to make that call “because I became convinced that Zelenskiy, the people around him, were legitimately trying to get rid of the corruption and get off the Russian gas.”

Perry met at least three times with Zelenskiy, including in May when he led a delegation to Ukraine’s presidential inauguration in place of Vice President Mike Pence. That trip was referenced in the whistle-blower complaint that sparked the House’s swift-moving impeachment inquiry.

Perry said he did not yet know if he would comply with a House subpoena for documents ahead of a deadline later Friday, deferring to a forthcoming recommendation from his general counsel. “I’m going to rely upon our general counsel to give me advice,” he said.

Perry insisted the Bidens never came up in conversations with Ukraine officials, though corruption was a mainstay. “We heard corruption in almost every conversation that we had talking about Ukraine and whether or not President Zelenskiy was going to come over here, because President Trump wasn’t going to send American money to a country that had a history of being corrupt,” Perry said. “And he was hammering that, and we hammered that.”

This article was provided by Bloomberg News.