Germany and France have led a sharp European response to President-elect Donald Trump's remarks that NATO is "obsolete" and more countries would leave the European Union after Britain.

In an interview with two European newspapers, Trump launched several broadsides at Europe and criticised Chancellor Angela Merkel's "catastrophic" decision to open Germany's borders to Syrian refugees.

With fears growing in Europe over Trump's commitment to the transatlantic alliance and signs he will pivot towards Russia, Merkel gave warning on Monday that the continent now had to take responsibility for itself.

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"We Europeans have our fate in our own hands," Merkel said in Berlin, when asked about Trump's criticisms, adding that she will work towards getting the EU to strengthen the economy and fight terrorism.

She said: "I'm personally going to wait until the American president takes office, and then we will naturally work with him on all levels".

President of France, Francois Hollande's response to Trump's intervention was more blunt, insisting that the EU "has no need for outside advice" on its affairs.

Criticism of NATO

Trump's latest remarks have, in particular, caused further concern among Eastern European NATO countries nervous about Russia, following President Vladimir Putin's annexation of Crimea and involvement in Ukraine.

"I said a long time ago that NATO had problems," Trump told The Times of London and Bild, Germany's biggest-selling daily, on Friday.

"Number one, it was obsolete, because it was designed many, many years ago," he said, referring to its Cold War, post-World War II origins.

"Number two, the countries aren't paying what they're supposed to pay."

On the campaign trail, too, Trump had said he would think twice about helping NATO allies if the US was not "reasonably reimbursed" for the costs of defending them - a common source of friction in the US-led 28-nation alliance.

Even so, the comments came as a bit of a surprise since his choice for defence secretary, James Mattis, stressed his support for the alliance in his US congressional confirmation hearings last week.

Frank-Walter Steinmeier, German foreign minister, said Europe was stunned by Trump's remarks on NATO, just five days before his inauguration as president.

"The interview statements of the American president-elect ... caused, indeed here in Brussels, astonishment and agitation," Steinmeier said as he went from a meeting with NATO chief Jens Stoltenberg to talks with EU counterparts.

Trump's views contradict those of Mattis, Steinmeier said.

His French counterpart Jean-Marc Ayrault said the best response to such an interview was simple: Europeans uniting.

Stoltenberg was "absolutely confident" in Trump's commitment to NATO, the alliance chief's spokesperson said.

'Courageous' Merkel

Nevertheless, criticism of Trump's comments came from the US.

John Kerry, the outgoing secretary of state, said on Monday that Trump had been wrong to criticise "courageous" Merkel.

Trump, however, further extended a hand to Russia, which has been hit by sanctions under Obama's outgoing administration over its involvement in Ukraine, the Syrian war and for suspected cyber attacks to influence the US election.

"Let's see if we can make some good deals with Russia," Trump said, suggesting in vague terms a deal in which nuclear arsenals would be reduced and sanctions against Russia eased.

In another comment that alarmed the Europeans, Trump refused to say that he trusted Merkel more than Putin, for whom he has often expressed admiration.

"Well, I start off trusting both - but let's see how long that lasts. It may not last long at all," he said.

Trump also directly criticised Merkel for letting Germany admit migrants and refugees, insinuating that this posed a security risk following a wave of attacks in Europe claimed by the Islamic State of Iraq and the Levant (ISIL) group.

"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," Trump said, adding he had "great respect" for Merkel.

Car makers warned

Trump further threatened punitive 35 percent tariffs on German car manufacturers such as BMW, if they build cars in Mexico and not the US.

In other remarks, Trump said Brexit "is going to end up as a great thing", and he backed a trade deal with post-EU Britain which would be "good for both sides".

"We're gonna work very hard to get it done quickly and done properly," said Trump, confirming he will meet Theresa May, UK prime minister, soon after his inauguration on Friday.

The British pound took a hit Monday after Britain said it might undercut the EU economically, if it cannot obtain both single market access and immigration controls, with British media warning of a "hard Brexit".

"Other countries will leave" the EU in future, Trump predicted, largely due to the pressure the bloc was put under following a surge in arrivals of migrants and refugees fleeing wars in Syria and elsewhere.

Federica Mogherini, EU high representative, however, said it was "absolutely clear" that Britain could not start any trade talks with the US until it leaves the bloc.

Source: News agencies