President-elect Trump heavily criticized Chancellor Merkel's open-door policy on refugees in a joint interview published on Sunday with German tabloid newspaper "Bild" and British newspaper "The Times."

"I think she made one very catastrophic mistake and that was taking all of these illegals, you know, taking all of the people from wherever they come from,” he said.

"And nobody even knows where they come from. So I think she made a catastrophic mistake, very bad mistake.”

In 2015 about 900,000 migrants, some coming from Syria, entered Germany after Merkel opened the country's doors, famously saying "we can do this."

The bilionaire businessman said Germany had "got a clear impression" of the consequences of her policy from a Berlin terror attack that killed 12 people in December.

Trump insisted he had "great ­respect” for Merkel and would start his presidency trusting the "fantastic leader," but that his trust might not last long.

Brexit deal

Trump promised he would offer the United Kingdom a trade deal within weeks of taking office to help make Brexit a "great thing.”

"We're going to work very hard to get it done quickly and done properly. Good for both sides,” Trump said.

"I will be meeting with [British Prime Minister Theresa May]. She's requesting a meeting and we'll have a meeting right after I get into the White House and it'll be, I think we're going to get something done very quickly.”

May said on Saturday she would lead the country towards a "hard Brexit."

Others will leave

Trump warned that other countries in the 28-member EU would follow suit after Brexit because of immigration.

"I think it's very tough,” he said. "People, countries want their own identity and the UK wanted its own identity.”

"If refugees keep pouring into different parts of Europe ... I think it's going to be very hard to keep it together because people are angry about it."

He said the mass arrivals in 2015 were "the last drop that made the barrel overflow" in convincing British voters to back leaving the bloc in a June 24 referendum.

"If they hadn't been forced to take in all of the refugees, so many, with all the problems that it... entails, I think that you wouldn't have a Brexit. This was the final straw that broke the camel's back."

He further said the European Union had become "a vehicle for Germany”.

Nato obsolete

Trump described the NATO alliance as an "obsolete" organization.

"I said a long time ago that NATO had problems. Number one it was obsolete, because it was designed many, many years ago," he said.

He insisted that NATO remained "very important to me," but that some NATO allies weren't paying enough.

"We're supposed to protect countries. But a lot of these countries aren't paying what they're supposed to be paying, which I think is very unfair to the United States."

"With that being said, NATO is very important to me. There's five countries that are paying what they're supposed to. Five. It's not much," he added.

US contributions to NATO accounted for about 70 percent of spending by the bloc's nations.

Taxes for BMW

He threatened German carmaker BMW with a border tax of 35 percent on cars that it planned to build at a new plant in Mexico and export to the US.

He told the German daily that BMW should instead build its new car factory in the US because this would be "much better" for the company.

A BMW spokeswoman said a new plant in San Luis Potosi would build the BMW 3 Series starting from 2019.

Merkel, who is facing elections later this year, criticized Trump's protectionist policies on Saturday, and earlier said there was no guarantee of cooperation between the two countries.

"From the point of view of some of our traditional partners - and I am thinking here as well about the transatlantic relations - there is no eternal guarantee for a close cooperation with us Europeans," Merkel told an audience in Brussels.

On Friday the outgoing US ambassador to the EU warned against Trump supporting the bloc's breakup, saying it would be "sheer folly."

Trump was interviewed for "The Times" by prominent Brexit campaigner and conservative British member of parliament, Michael Gove and for "Bild" by its publisher and former editor Kai Diekmann, a prominent German journalist who will soon depart the business.

aw/kl (dpa, AFP, Reuters)