US president-elect Donald Trump criticized the European Union and Germany for their immigration policies in a joint interview published Sunday by Britain's The Times and Germany's Bild newspapers. Trump said more countries could leave the EU over migration, and said Germany in particular had made a mistake letting in too many refugees. "If refugees keep pouring into different parts of Europe ... I think it's gonna be very hard to keep it together because people are angry about it," Trump said. He said Brexit wouldn't have occurred if Britain hadn't been forced to take in so many migrants. "People, countries, want their own identity and the UK wanted its own identity," he said, adding "I believe others will leave." He sees the EU as "basically a vehicle for Germany," and said that's why he thought Britain "was so smart in getting out." Trump expressed admiration for German Chancellor Angela Merkel in the interview, but also said she made a mistake by welcoming too many refugees into Germany. "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. And nobody even knows where they come from," Trump said. He said safe zones should have been built for Syrians in Syria to limit the migration surge. On trade issues, Trump said he would move quickly to seal a new trade deal with Britain and that British Prime Minister Theresa May would be visiting him "right after" he gets into the White House. "We're gonna work very hard to get it done quickly and done properly. Good for both sides," he said. Trump said Germany had been "unfair" to the US, noting that there are a lot of Mercedes sold in the US, but Germans don't buy a lot of Chevrolets. It's a "one-way street," he said. He warned against German automakers building manufacturing plants in Mexico with plans to ship cars to the US. He would support a 35 per cent import tax on those vehicles, he said. On Russia, the 70-year-old suggested a review of sanctions if President Vladimir Putin is prepared to move away from confrontation. "Let's see if we can make some good deals with Russia, Trump said. "I think something can happen that a lot of people are gonna benefit." Trump used the hour-long interview, which took place in his office in Trump Tower in New York, to again voice his criticism of NATO countries not paying enough into the military alliance. He also said NATO's design is obsolete because it isn't focused on fighting terrorism. But, he emphasised that NATO remains important and that he is committed to the defence of Europe and the West. Trump also had a message for his many social media followers too, with the avid tweeter saying he will continue using Twitter despite criticism for his shoot-from-the-hip approach. The social media platform gives him a direct connection to his millions of followers and a way around the media, he said.