President-elect Donald Trump wants to stop the spread and ultimately defeat "radical Islamic terrorism," said Kellyanne Conway, who was named on Thursday as counselor to the president.
Trump had "talked about that on the campaign trail," she said on CNBC's "Squawk Box." "It's part of why he won."
The deadly terrorist truck attack on a Berlin Christmas market on Monday shows the need for "extreme vetting" of people who want to come into the United States, Conway said.
"Extreme vetting" stops short of onetime calls by Trump during the campaign to ban Muslims from entering the U.S., a position later clarified as stopping people from countries that have a history of Islamic extremism.
German authorities said the prime suspect sought in the Berlin assault — 24-year-old Tunisian national Anis Amri — had been scheduled to be deported after the rejection of his asylum application but for a delay in the paperwork. Amri had also been under surveillance on suspicion that he had become radicalized, officials said.
Trump wants to join with allies of the U.S., "and even those we don't work that closely on in other matters, to come together and defeat radical Islamic terrorism," Conway said.
"He wants to have more extreme vetting in place in [regard to] countries that harbor and train and export terrorists," she said.
"This is simple to understand," Conway added, highlighting the people and regions that should be scrutinized. "You go where the hot spots are, you go where the training is, you go where people are looking to do harm and bring death and destruction on civilized people."