(CNN) Donald Trump's latest proposal to stop immigration "from any nation that has been compromised by terrorism" is an "expansion" of his blanket ban on Muslims, he said in an interview that aired Sunday.

Trump has not defined which countries would be included in that list of territories, but on "Meet the Press" Sunday, he refused to rule out banning individuals from top US allies like France and Germany, saying that "they have totally been" compromised by terrorism.

Trump had previously said that if elected he would "suspend immigration from areas of the world when there is a proven history of terrorism against the United States, Europe or our allies, until we understand how to end these threats."

What would that version -- there have been several -- of the GOP nominee's proposed ban look like? And how many people would it affect? The short answer is millions. Here's the math, including based on tallying nonimmigrant and immigrant visas from countries that have any sort of terrorist activity:

Start with 'terrorist safe havens': 12 countries; 496,436 nonimmigrant and 74,283 immigrant visas in 2015

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