“Just an idea,” tweeted David Bossie, president of the conservative activist group Citizens United and a trusted friend of President Donald Trump.

“@realDonaldTrump should consider releasing President Obama’s phone conversations with world leaders. Say the one with Iran before the pallets of cash boarded the plane.”

The U.S. flew $400 million to Iran in 2015 under the Obama-negotiated nuclear deal as part of a settlement relating to a pre-revolution arms deal that was never completed.

Trump is facing impeachment in part over his conduct on a July 25 call with Ukraine’s President Volodymyr Zelenskiy.

The White House has released an edited summary of that call but has withheld a full transcript of the conversation.

In the summary, Trump is seen asking Zelenskiy for a “favor” and two open two investigations, one into the Democratic Party and another into former Vice President Joe Biden, one of its leading candidates for the 2020 nomination.

House Democrats, who have opened an impeachment inquiry, accused Trump of seeking the help of a foreign government to interfere to his benefit in the next election.

Trump denies any wrongdoing. But the two investigations he wanted are based on allegations that are either conspiracy theory or spurious.

One was into the discredited conspiracy theory that the DNC conspired with the cybersecurity company CrowdStrike to frame Russia for election meddling, and that the evidence is held on a server in Ukraine.

The other was into dubious accusations of corruption leveled at Biden and his son Hunter Biden, who sat on the board of a Ukrainian gas company called Burisma.

According to The New York Times, Lieutenant Colonel Alexander Vindman, the National Security Council’s Ukraine expert, told the House impeachment inquiry that multiple important words and phrases were not included in the summary of the Trump-Zelenskiy call. Vindman had sat in on the call at the time.

Bossie is a longtime friend of Trump’s and was considered to be a close confidant.

But the president distanced himself from Bossie back in May amid accusations that he scammed elderly and middle-class supporters of the president, Politico reported.

According to Axios, only a small portion of the millions raised by Bossie’s group the Presidential Coalition, largely from small-dollar donors, was used to back the campaigns of Trump-supporting conservative candidates as it had pledged to do.

The former Trump campaign aide denied misleading donors. Some of the money was reportedly used to pay external consultants with which Bossie was connected and to buy books he wrote.

By September, The Daily Beast reported that Trump and Bossie had made up.