WASHINGTON - A day after President Donald Trump awarded the massive Group of Seven summit to his own struggling Doral resort in Florida, the White House said Trump's company would only charge taxpayers enough to cover the resort's costs.

But neither the White House nor the Trump Organization answered more detailed questions about what that means. They did not provide specific dollar amounts or say if dollar amounts have been agreed to.

"Everything will be done at cost due to the emoluments clause," White House spokeswoman Stephanie Grisham wrote in an email message, "which means the summit would be significantly cheaper for taxpayers and our foreign guests."

She was referring to the Constitution's emoluments clauses, which say that presidents cannot accept payments from foreign governments or payments from the U.S. government in excess of his presidential salary.

Trump's decision brought a flood of criticism Friday from Democrats, including Sen. Richard Blumenthal, D-Conn., one of more than 200 Democrats who are suing Trump for past alleged violations of the foreign emoluments clause.

Blumenthal said they would add the Doral decision to their next legal filing, since it shows that Trump is accelerating his efforts to gain foreign-government business.

"Here he is, in plain sight, saying in effect, 'I'm just going to make your case for you,'" Blumenthal said.

For Trump, the potential benefits of awarding himself the summit go beyond the actual payments made by U.S. and foreign governments. There is also international media exposure that comes with the summit - putting Trump Doral on televisions and websites around the world.

Resorts that have hosted the summit of world leaders, including the Lough Erne resort in Northern Ireland in 2013, have seen increased exposure and improvements in their business for years after the summit. "Lough Erne wouldn't be the place it is today without the PR and the legacy of that event," William Kirby, the resort's general manager, said recently. "It's the pinnacle of the resort history."

That summit boosted the local economy and highlighted the resort on the world stage, he said. "You can't buy that, can you?" Kirby said.

The White House appeared to be saying that Trump was going to take payments from both foreign governments and the U.S. government - but that he believed that was fine, as long as he didn't set out to make a profit. Typically, the U.S. government pays the bulk of costs for hosting a summit, but foreign countries pay for their own rooms.

Grisham also said that the government might set up a host committee for the event, which could raise private donations. In that case, it would give private donors a chance to pay the president's company - saving taxpayers money, perhaps, but creating new questions about conflicts of interest.

The Trump Organization did not respond to questions about the event on Friday.

On Thursday, the White House announced that it would hold the 2020 summit at Doral, a resort near the Miami airport that Trump bought in 2012. The resort is a keystone of Trump's finances, but it has been in sharp decline recently: from 2015 to 2017, the resort's net operating income fell 69 percent.

The summit is scheduled for June, which is typically one of the resort's slowest months with less than 40 percent of rooms occupied, and will likely fill the hotel with hundreds of diplomats, journalists and security personnel.

There was a trickle of criticism from Republicans on Capitol Hill.

"I don't understand why at this moment they had to do that," said Rep. Adam Kinzinger, R-Ill., on CNN, calling the move "unnecessary" and adding, "I wouldn't do it." Kinzinger said he had defended Trump on the controversy of allowing Department of Defense crews to stay at Trump property in Scotland, but said, "this is something that feels a little different."

Rep. Francis Rooney, R-Fla., said: "In the law, there's a canon that says, 'Avoid the appearance of impropriety.' I think that that would be better if he would not use his hotel for this kind of stuff."

In Brussels, where European leaders were gathered for meetings, European Council President Donald Tusk, an invitee to past G-7 summits, said it was not appropriate to spend public funds at Trump's resort. "Not at all," he said.

Tusk is expected to step down from his role next month, but for the last five years he has been a participant in the Group of Seven summit. His successor, current Belgian Prime Minister Charles Michel, will have to make the final decision about whether and how to participate in the summit.

German Chancellor Angela Merkel, also asked by The Washington Post at a news conference whether she was ready to spend German tax money on Trump's private business, said that "this is a decision taken by the American president. I haven't had time to deal with this yet. We will take a close look at his invitation, and my intention is to attend the summit."

Already, Trump's decision is the subject of questions in Germany, where the leader of a far-left opposition party asked Friday whether the money should be channeled to Trump's business.

"Heads of state and government aren't in favor of financing his business," Left Party head Bernd Riexinger told the Agence France-Presse newswire.

"President Donald Trump is mixing private and state interests with his decision to place heads of state and government in one of his hotels," he said. "This behavior is harmful for democracy."

The budget for the 2013 summit in Northern Ireland - most of it paid for by Prime Minister David Cameron's British government - was reportedly more than $100 million.

The 2018 summit, held at the Fairmont Le Manoir Richelieu north of Quebec City in Canada, provided a tourist boost for the region, according to an official in the regional tourist authority.

Hotel occupancy for June 2018, the month of the summit, got a nearly 20 percent bump over the prior June, pushing the region to its first year of more than 50 percent hotel occupancy.

"I cannot guarantee it's completely because of the summit but it really helped because April to June are not the high season. Those months were definitely good," said the official, who was not authorized to speak publicly.

"What we can say is that it's been good for visibility for the region for sure to see the name Charlemoix everywhere," the official said. "It's been good for the tourism performance."

The White House has said that the Doral was clearly the best of the 12 possible sites that it vetted for the event but it has declined to name the other 11 sites. The one detail given about other sites was that one was so high-altitude that the planners thought they might have to provide oxygen tanks for participants.

"Out of an abundance of caution, that site was eliminated," Grisham said.

The White House has not explained how Trump would estimate the cost of hosting visitors at a resort whose expenses include staff, administration, maintenance and debt payments. It also hasn't said if any outsider could challenge Trump's estimate: In this unprecedented transaction, Trump is effectively negotiating with himself, as both buyer and seller, with taxpayers paying the bill.