Sen. Lindsey Graham (R-S.C.) slammed House Democrats on Wednesday for holding a public hearing with Michael Cohen, President Donald Trump’s disgraced former lawyer, on the same day that Trump is negotiating in Vietnam with North Korean leader Kim Jong-un at a high-stakes summit.

The Cohen hearing before the House Committee on Oversight and Government Reform is overshadowing the president’s second summit with Kim in Vietnam as the two discuss North Korea’s denuclearization progress.

Cohen found himself in special counsel Robert Mueller’s crosshairs.

The former attorney claimed Trump directed him to violate federal campaign finance laws to influence the 2016 presidential election by making hush-money payments to two women who have claimed they had affairs with Trump — something the president denies.

Related: Jim Jordan Questions Why Admitted Liar Michael Cohen Is Testifying Before Congress 

Cohen has pleaded guilty to charges of lying to Congress about his business dealings with Russia and the Trump Organization during the 2016 campaign.

His prison sentence will begin in May.

During his opening statement on Wednesday, Cohen said, “I am ashamed that I chose to take part in concealing Mr. Trump’s illicit acts rather than listening to my own conscience.” He also accused the president of directing “a criminal scheme to violate campaign finance laws.”

The timing of Cohen’s hearing infuriated Graham.

“New Low for House Democrats: Holding hearings with Michael Cohen while President @realDonaldTrump negotiates with North Korea about giving up their nuclear arsenal,” Graham tweeted. “Democrats’ hatred of Trump is undercutting an important foreign policy effort and is way out of line.”

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“If Republicans had pulled such a stunt — the mainstream media would be outraged,” Graham added.

Republican National Committee (RNC) chairwoman Ronna McDaniel also slammed House Democrats for holding the public hearing as Trump negotiates with Kim this week.

Related: Sarah Sanders Calls Michael Cohen a ‘Liar’ on First Day of Hearings

“During President Obama’s last year in office, North Korea was firing a missile every 24 days. Under @realDonaldTrump, it’s been 457 days without a missile launch. Now Democrats are using Michael Cohen — an established liar — to distract from this historic progress overseas,” McDaniel tweeted.

“Let’s be clear: This is a total sideshow to distract from @realDonaldTrump’s accomplishments overseas. Democrats have invited someone to testify to Congress who is literally going to jail, in part, for lying to Congress under oath,” McDaniel continued.

Trump told reporters on Wednesday he “thought the first summit was a great success and I think this one, hopefully, will be equal or greater than the first.”

The president did not answer reporters’ shouted questions about the Cohen hearing and his allegations against Trump.

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