Meanwhile, the Swedish embassy has responded to his remarks on the non-existent terror incident
Donald Trump has said his reference to a non-existent incident in Sweden was based on a TV report he had seen on Fox News.
The President had left many people scratching their heads - including the Swedish government - after he falsely suggested there was an immigration-related security incident in the country on Friday night.
Illustrating his point about the relationship between terror attacks and refugees, he had told a rally in Florida on Saturday afternoon: "You look at what's happening in Germany. You look at what's happening last night in Sweden. Sweden! Who would believe this? Sweden! They took in large numbers, they're having problems like they never thought possible.
"You look at what's happening in Brussels. You look at what's happening all over the world. Take a look at Nice. Take a look at Paris.
"We've allowed thousands and thousands of people in to our country and there was no way to vet those people. There was no documentation. They was no nothing. So we're going to keep our country safe."
No such incident had occurred - and hours after baffled Swedish officials asked the US State Department for clarification on Mr Trump's remarks, he tweeted: "My statement as to what's happening in Sweden was in reference to a story that was broadcast on @FoxNews concerning immigrants & Sweden."
My statement as to what's happening in Sweden was in reference to a story that was broadcast on @FoxNews concerning immigrants & Sweden.— Donald J. Trump (@realDonaldTrump) February 19, 2017
Fox News had ran a report on Friday night about alleged migrant-related crime problems in the country - and it is possible Mr Trump was confusing clips from the documentary with a real-time event.
According to a White House spokeswoman, Mr Trump had been referring generally to rising crime in Sweden, but not a specific incident in the Scandinavian country.
Meanwhile, the Swedish embassy in the US has responded to Trump on Twitter, saying: "We look forward to informing the US administration about Swedish immigration and integration policies."
We look forward to informing the US administration about Swedish immigration and integration policies. https://t.co/x5G3euOWRh— Embassy of Sweden US (@SwedeninUSA) February 19, 2017