LONDON — President Donald Trump came out swinging at friends and foes here Tuesday, accusing Democrats of being "unpatriotic" and calling remarks by French President Emmanuel Macron "very, very nasty."

“I think it's very unpatriotic of the Democrats to put on a performance where they do that,” Trump said of the House impeachment inquiry, in his first public comments since arriving in London. “I do. I think it's a bad thing for our country. Impeachment wasn't supposed to be used that way.”

Later in the day, with Canadian Prime Minister Justin Trudeau seated at his side, Trump called House Intelligence Committee Chairman Adam Schiff, D-Calif., "a maniac" and a "deranged human being."

The president also rattled markets by suggesting trade deal negotiations with China might not end until after the election next year.

Trump made the remarks during a trio of wide-ranging question-and-answer sessions. The president spent more than two hours over the course of the day talking to reporters, announcing during his session with Trudeau that next year's G-7 meeting — originally destined for his Doral resort in Florida, amid controversy — would be held at Camp David.

While Trump did have a day of meetings planned with world leaders to review the current status on a range of issues and areas — including Syria, Iran and China — his moment on the international stage was at risk of being upstaged by the intensifying impeachment inquiry back home.

The House Intelligence Committee is due to deliver to the Judiciary Committee its report on the president's dealings with Ukraine. This included witnesses testifying to the particulars of Trump freezing aid to that country while directing top lieutenants to work through his personal lawyer, Rudy Giuliani, to pressure officials in Kyiv to open investigations into the Bidens and a conspiracy theory that claimed Ukraine framed Russia for interfering in the 2016 election.

The House Judiciary Committee's first impeachment hearing is scheduled for Wednesday when Trump will be holding another day of meetings here. Trump said he and administration officials wouldn't testify in the hearings because the process isn't fair, but suggested he might when it is in the Senate.

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"So when it’s fair, and it will be fair in the Senate, I would love to have Mike Pompeo, I would love to have Mitch, I’d love to have Rick Perry, and many other people testify," Trump said. "I don’t want them to testify when this is a total fix.”

He added that he didn't expect the inquiry to affect his discussions at the gathering.

“I know most of the leaders, I get along with them. It’s a hoax. The impeachment is a hoax. It’s turned out to be a hoax. It’s done for purely political gain," Trump said.

'Very, very nasty'

In a sign the relationship between Trump and Macron may be souring, Trump called recent comments by the French president critiquing NATO "insulting" and a “very, very nasty statement.” Trump went on to criticize Macron’s handing of France's economy.

Macron, who will meet with Trump later in the day, recently warned European allies that they could no longer rely on America to help defend them and that “what we are currently experiencing is the brain death of NATO.”

Trump, who as a candidate called NATO “obsolete,” once again threatened to tax French wine in retaliation for a French tax on U.S. tech companies, saying that "if anyone is going to take advantage of those companies it would be the U.S."

“You have a very high unemployment rate in France. France is not doing well economically at all,” Trump said. He added that “they had a very rough year, and you just can't go around making statements like that about NATO. It's very disrespectful.”

Following a meeting with Macron, Trump described Macon as a "partner" and said the trade dispute between them was a "minor dispute." But the diverging views could be seen between the pair on a range of topics from the purpose of NATO and the European Union to what to do about Syrian fighters.

At one point Trump joked about ISIS prisoners, saying to Macron, "Would you like some nice ISIS fighters? I could give them to you."

Macron responded by saying, "let's be serious" and adding that "it is true you have foreign fighters coming from Europe, but this is a tiny minority of the overall problem."

On China, Trump suggested he may wait until after the election to sign a trade deal, after repeatedly saying he was close to getting a deal done. The protracted trade war has been a point of contention with the other European allies.

“In some ways, I like the idea of waiting until after the election for the China deal,” Trump said.

Trump has had a tumultuous past with NATO. At his first summit, he shocked leaders when he failed to reaffirm a core principle of the alliance — that an attack against one member is an attack on all. During last year’s gathering, he threatened that if members didn’t immediately increase their defense spending, the U.S. would pull out of the alliance.

Trump touted his success at squeezing more money out of America’s allies to spend on their militaries, including South Korea. He said he met with South Korean officials six or seven months ago and told them “you have to pay up” because they weren’t spending enough on their defense while the U.S. was sending billions. Trump said after the conversation, South Korea added $500 million to its military budget.

There was no immediate reaction from Seoul to Trump's statements.

Trump also took credit for NATO member countries increasing their spending on the alliance by about $130 billion from 2016 to 2020, higher than previously forecast.