Updated at 9:10 a.m. Sunday with details from Sen. Ron Johnson

President Donald Trump is reportedly blaming the former Texas governor in his Cabinet for proposing his July 25 call to the new Ukrainian leader.

Energy Secretary Rick Perry, who has become a recurring figure in the Trump administration's dealings with Ukraine, encouraged Ukrainian President Volodymyr Zelenskiy to tackle corruption while also urging him to change the way his nation manages its oil and gas interests, Politico reported Saturday.

Trump's dealings with Ukraine — specifically, asking Zelenskiy to investigate former U.S. Vice President Joe Biden and his son Hunter — have formed the basis of a U.S House impeachment inquiry.

In other developments, an article posted Saturday by online news agency Axios reported that Trump told House Republicans that it was Perry who urged him to make the initial phone call to Zelenskiy — a call that Trump has characterized as "perfect."

Axios reported that Trump told the GOP "something to the effect of, 'Not a lot of people know this but, I didn't even want to make the call. The only reason I made the call was because Rick asked me to.'"

President Donald Trump and Ukrainian President Volodymyr Zelenskiy look on during a meeting in New York on the sidelines of the United Nations General Assembly last month. (SAUL LOEB / AFP via Getty Images)

So far, text messages released in recent days indicate that Trump's personal attorney, former New York City Mayor Rudy Giuliani, was the inspiration behind the phone call to Zelenskiy. The messages appear to contradict Trump's mention of Perry.

A spokesman for Perry told Axios that any call Perry urged Trump to make focused exclusively on regulatory matters and economic development.

In addition, Perry vehemently denied mentioning either of the Bidens in any official conversations about Ukraine.

"I never heard, and I talked to the president about this," Perry said in an interview with the Christian Broadcasting Network. "I had a conversation with -- a phone call -- with Rudy Giuliani about it. I've talked to the previous ambassador. I've talked to the current ambassador. I've talked to Kurt Volker, Gordan Sondland, the EU ambassador -- every name that you've seen out in the media and not once, not once, as God is my witness, not once was a Biden name -- not the former vice president, not his son -- ever mentioned."

Politico's report also indicated there was no evidence that Perry mentioned the Bidens in any conversation with Ukrainian officials.

Instead, Perry pushed for an expansion of the board that serves the country's state-owned natural gas company so that Americans might sit on it, adding that two Texas-based energy executives were interested in serving.

Perry has cultivated extensive ties in Ukraine. He attended Zelenskiy's inauguration and met in June 2017 with former Ukrainian President Petro Poroshenko at the Energy Department headquarters in Washington. He met several top officials on a visit to Ukraine last November and interfaced with a Ukrainian delegation in early May at a conference in Brussels.

Sen. Ron Johnson, R-Wis., a leader of the Senate's Ukraine caucus, joined Perry on the trip in May, and afterward in the Oval Office to brief Perry.

"We were trying to encourage the president to show a great deal of support" in backing the new leader, he told reporters in Wisconsin on Friday.

He indicated that at the time, he didn't know of any linkage Trump made between aid and Ukraine committing to open a corruption investigation aimed at Biden and his son.

Johnson told the Wall Street Journal that Sondland -- the U.S. ambassador to the European Union and a former hotel executive and major Trump donor -- told him ahead of another visit to Ukraine in September that military aid to Ukraine was being linked to Trump's desire to have Zelenskiy's team investigate the 2016 U.S. elections.

"At that suggestion, I winced," Johnson told the Journal. "My reaction was: Oh, God. I don't want to see those two things combined."

On Friday, Johnson told reporters in Sheboygan, Wis., that when he asked Trump if he could assure Ukraine's leadership that the money would be coming, the president blocked him from doing so.

House committees investigating Trump released text messages last week showing Sondland and other diplomats trying to broker a meeting between Trump and Zelenskiy, on the condition that Ukraine open an investigation into a gas company where Hunter Biden had served on the board.

Despite Trump's actions, Johnson said he believes Trump's assertion that his motive was to root out corruption in a key Eastern European ally.

"I take what President Trump is saying at face value," said Johnson.

Staff writer Tom Benning contributed to this report.