NEW YORK (AP) — Facing intense scrutiny from President Donald Trump and his Republican allies, Hunter Biden said Sunday he will step down from the board of directors of a Chinese-backed private equity firm at the end of the month as part of a pledge not to work on behalf of any foreign-owned companies should his father win the presidency.

Biden, the 49-year-old son of Democratic presidential candidate Joe Biden, revealed his plan in an internet post written by his attorney, George Mesires, who outlined a defense of the younger Biden’s work in Ukraine and China, which has emerged as one of Trump’s chief lines of attack against Hunter’s father despite no proof of impropriety.

“Hunter makes the following commitment: Under a Biden Administration, Hunter will readily comply with any and all guidelines or standards a President Biden may issue to address purported conflicts of interest, or the appearance of such conflicts, including any restrictions related to overseas business interests. In any event, Hunter will agree not to serve on boards of, or work on behalf of, foreign owned companies,” Mesires wrote.

He continued: “He will continue to keep his father personally uninvolved in his business affairs, while availing himself as necessary and appropriate to the Office of the White House Counsel to help inform his application of the Biden Administration’s guidelines or standards to his business decision-making.”

Joe Biden, speaking to reporters after a union forum in suburban Des Moines, Iowa, said his son did not discuss that decision with him before posting the statement.

“No one has asserted my son did a single thing wrong,” Biden added, pounding his finger into the podium, “except a lying president.”

And Biden promised to bar his family members from occupying any office within the White House and said they won’t “sit in meetings as if they are a Cabinet member.” That was a jab at Trump, who taps daughter Ivanka and her husband, Jared Kushner, as advisers. Biden did not say if his pledge meant that Jill Biden, his wife, would not get the office traditionally assigned to first ladies, should he win.

He further vowed that no one in his family will have “any business relationship with anyone that relates to a foreign corporation or foreign country.”

Hunter Biden’s work overseas sits at the center of the House impeachment inquiry into Trump, who has admitted to asking foreign powers to investigate Hunter Biden’s business dealings abroad.

The White House released a rough transcript of a call in which Trump asks Ukraine’s new president, Volodymyr Zelenskiy, to probe Biden’s family and Ukraine’s role in the 2016 election that put Trump in office. Trump has also encouraged China to dig into Hunter Biden’s work in that country, asserting without evidence that earned $1.5 billion from a “sweetheart” business deal there.

The president’s personal attorney, Rudy Giuliani, is also under increasing scrutiny for his efforts to dig into Hunter Biden’s business background. Late last week, two businessmen involved in Giuliani’s efforts to investigate Hunter Biden’s dealings in Ukraine were charged with federal campaign finance violations.

Still, Republicans reacted to news of Hunter Biden’s decision to step away from the Chinese-backed BHR Equity Investment Fund Management Co. with deep skepticism.

“I think this is just another way to save a flailing campaign that’s going down,” Georgia Rep. Doug Collins, the top Republican on the House Judiciary Committee, said on Fox News Channel’s “Sunday Morning Futures.” ″He knows he’s in trouble and this is just another way to try and detract attention

On the same show, White House counselor Kellyanne Conway said Hunter Biden “should have done this quite a while ago.”

Mesires noted repeatedly that there is no evidence of wrongdoing against Hunter Biden, despite intensifying attacks from Trump before the 2020 election.

“Despite extensive scrutiny, at no time has any law enforcement agency, either domestic or foreign, alleged that Hunter engaged in wrongdoing at any point during his five-year term,” Mesires said in his Sunday post of Biden’s experience in Ukraine.

The attorney wrote that Hunter Biden worked as an unpaid board member for BHR Equity Investment Fund Management Co. “based on his interest in seeking ways to bring Chinese capital to international markets.”

“To date, Hunter has not received any compensation for being on BHR’s board of directors,” Mesires said. “He has not received any return on his investment; there have been no distributions to BHR shareholders since Hunter obtained his equity interest.”

One of Biden’s Democratic presidential rivals praised the move, noting that Trump’s children are openly trading on his name in business deals around the world while Trump occupies the Oval Office.

“I think it demonstrates the difference in standards relative to the White House,” said Pete Buttigieg, the mayor of South Bend, Indiana.

“I mean, here you have Hunter Biden stepping down from a position in order to make sure, even though there’s been no accusation of wrongdoing — doing something just to make sure there’s not even the appearance of a conflict of interests, while, in the White House, the president of the United States is a walking conflict of interest,” he said.