You can pretty much guarantee the Brits will cave and let them stay.

Via The Times:

Banning the Muslim Brotherhood will leave Britain at greater risk of terrorist attacks, the group’s most senior leader in the UK said yesterday.

Speaking for the first time since David Cameron announced an investigation into the organisation’s alleged links to violent extremism, Ibrahim Mounir said that it risked alienating moderate Muslims. “If this [ban] happened, this would make a lot of people in Muslim communities think that [peaceful] Muslim Brotherhood values . . . didn’t work and now they are designated a terrorist group, which would make the doors open for all options,” he said.