Trump National Doral Miami is a golf resort in south Florida.

President Donald Trump was forced to abandon his decision to host next year's Group of Seven summit at his private golf club after it became clear the move had alienated Republicans and swiftly become part of the impeachment inquiry that threatens his presidency.

In a round of phone calls with conservative allies this weekend, Trump was told Republicans are struggling to defend him on so many fronts, according to an administration official who spoke on the condition of anonymity to discuss internal matters.

Democrats, meanwhile, continued to blast Trump for awarding the massive government contract to his own company and said they might add the alleged "emoluments" violation to the articles of impeachment they are preparing.

The White House has been struggling to explain Trump's G-7 decision since it was announced Thursday. The president's opponents quickly seized on it as another example of Trump abusing his office for personal gain. Even many Republicans seemed reluctant to offer political cover.

White House acting chief of staff Mick Mulvaney tried to defend the decision during a news conference but caused a new controversy when he was asked about Trump's call with the Ukrainian president that sparked the impeachment inquiry. Mulvaney told reporters that Trump had held up nearly $400 million in aid to push the foreign government to investigate Democrats, comments that undercut Trump's central defense in the inquiry. When a journalist followed up, saying that Mulvaney seemed to be describing a quid pro quo, Mulvaney said "we do that all the time with foreign policy."

On Sunday, Mulvaney expressed regret about how he handled the two issues.

"It's not lost on me that if we made the decision [to move the G-7] on Thursday, we wouldn't have had the news conference on Thursday regarding everything else, but that's fine," he said on "Fox News Sunday."

Mulvaney's acknowledgment of a mistake - he also said Sunday that the news conference had been less than "perfect" - comes as Trump has privately expressed displeasure with his acting chief's job performance and as some White House officials are seeking to replace him, according to several people familiar with the matter who spoke on the condition of anonymity to reveal private discussions. Several officials said Trump's aides and allies are considering options for a new chief of staff.

On Friday, White House press officials said Trump continued to support Mulvaney. "Mick Mulvaney's standing in the White House has not changed," White House spokeswoman Stephanie Grisham said.

But the chief of staff may have damaged that standing with his Fox News interview, in which he explained Trump's desire to host the G-7 at his property by saying the president "still considers himself to be in the hospitality business."

While several Trump allies said the comment was accurate, they said it was a bad idea for Mulvaney to make it in public. Other top Republicans, including Secretary of State Mike Pompeo, have begun to distance themselves from Mulvaney, who released a statement Thursday denying his admission of a quid pro quo.

Trump blamed his G-7 reversal on critics, saying on Twitter that his decision to scrap plans for a summit at the Doral club was "based on both Media & Democrat Crazed and Irrational Hostility."

But behind closed doors, several aides and allies said, Trump changed his mind in response to pressure and frustration from his own party.

In the month since Democrats announced their impeachment inquiry, Republicans have struggled to offer a coherent response. With no White House war room, GOP lawmakers have seized on a series of process-related responses.

At the same time, they're being asked to defend the president's erratic approach to policymaking, including his abrupt decision to withdraw U.S. troops and abandon Kurdish fighters in northeastern Syria. That announcement was roundly condemned by Republicans, including some of his staunchest defenders. Senate Majority Leader Mitch McConnell of Kentucky, in a rare public rebuke of Trump, wrote a withering op-ed in The Washington Post on Friday, just days after 129 House Republicans backed a resolution criticizing the president's move.

Trump's decision to host next year's G-7 meeting at his private golf club only increased the anxiety among GOP lawmakers, some of whom have grown weary of having to develop new talking points almost daily.

Privately, and occasionally in public, several Republicans said they were not prepared to defend the president from charges that he was engaged in self-dealing on the G-7 site selection.

Rep. Francis Rooney, R-Fla., said Friday that Trump should avoid even the appearance of impropriety that comes with holding a global summit at his private property. "I think that would be better if he would not use his hotel for this kind of stuff," he said.

Rooney, who announced his retirement the day after his comments, also said he was considering backing Trump's impeachment over his handling of Ukraine policy.

Trump has been closely watching Republicans and their comments about impeachment, according to one administration official. The president was told repeatedly his G-7 decision made it more difficult to keep Senate Republicans in a unified front against impeachment proceedings, the official said. Before he changed course, Trump had waved off concerns from advisers who said hosting world leaders at his club would not play well.

"There was very little support for this in the building even before Mick went out there and did what he did," an official said.

Before he took office, Trump made the unprecedented decision to keep ownership of his businesses - but he promised that he would never use his new power to help them. The Trump Organization's lawyers promised to avoid even the appearance of "any advantage derived from the Office of the Presidency."

But in practice, Trump has continued to boost his businesses - by talking them up and by visiting them repeatedly, with aides and fellow Republicans in tow.

Trump has visited his properties more than 130 times while in office. As of this summer, those visits had brought him more than $1.6 million in payments from the federal government and Republican campaign groups, which rented Trump's ballrooms for fundraisers.

In the past 18 months, Trump has made even more expensive visits to his properties in Ireland, Scotland and South Florida - visits that took him far out of his way from the official business of his trips. He also suggested Vice President Pence do the same: Pence built his own detour into an official trip and spent extra hours commuting so he could stay at Trump's club in remote southwestern Ireland. These trips bring attention to Trump's properties, and they bring revenue.

Democrats and good governance groups have said Trump is violating the Constitution's ban on receiving "emoluments" from foreign or domestic sources while president. The decision to host world leaders and U.S. officials at his Doral club during the G-7 was particularly controversial because it would have put Trump at the center of those alleged violations.

"It shouldn't have been done in the first place," Chris Christie, the former Republican governor of New Jersey, said Sunday on ABC's "This Week." "This was just an unforced error."

Christie said Trump should not be antagonizing Republicans at a time when he will need their votes to protect him in the impeachment process.

"We have to be in friend-making mode," he said.

Trump, who has been able to rely on near-unanimous Republican support during his 33 months in office, appeared chastened by the lack of support.

"I thought I was doing something very good for our Country by using Trump National Doral, in Miami, for hosting the G-7 Leaders," he tweeted Saturday.

One former senior administration official said Trump would regularly brag about his properties and ask visitors their opinions while boasting of their amenities.

"It's true that he really just thinks his properties are the best," said a longtime adviser to the president. "He does not understand in his mind why he would have something at someone else's property."

The president's critics were less charitable, accusing Trump of trying to make money for his private business by awarding himself a lucrative federal contract.

"This is why he ran in the first place," said Tim O'Brien, a Trump biographer and critic. "He never thought he'd win. It was free marketing."

Mulvaney, who claimed Thursday that the White House had chosen the president's Doral resort after a nationwide search, said Sunday on Fox that Trump was surprised by the backlash he had received.

"Could we have put on an excellent G-7 at Doral? Absolutely," he said. "Will we end up putting on an excellent G-7 someplace else? Yes, we will."