As I've already said, but will repeat, immigration of Muslims isn't where the problem lies. I realize there's a growing Muslim population in GB. My comment was pertinent specifically to your question. Populism isn't coming from the Muslim population, that's for sure. Populism is on the rise specifically because of the increasing Muslim population. Refugee flows and fear of Islam is what's driving right-wing support.
The US has one of the smallest Muslim populations among the major Western democracies, but anti-Islam sentiment, since Trump became president, has become a routine point of contention in politics. Few things in the US can present partisan party affiations more than attitudes toward Muslims and Islam. This simply was never the case, but it is now. In the minds of today’s European populist right, Muslims, regardless of their country of origin or date of immigration, share more in common with each another than with non-Muslim Europeans and thus are viewed as both a challenge and a threat to narrowly defined “values.” Populists see Islam’s doctrines as a threat to their values and civilization.
Once again, the rise in populist movements isn't because of the immigration of Muslims, it's the disinterest or objections on how to fully integrate a Muslim population into an already defined and established society.