MARTIN McGuinness is to resign his Mid-Ulster Westminster seat to concentrate on his role as Deputy First Minister.
The move is part of a Sinn Fein shake up to end double jobbing.
The Mid-Ulster MP will now apply to leave Westminster, which when complete will force a by-election in his former constituency - predicted to take place in the autumn.
Four other Sinn Fein MPs are also to resign from their Assembly roles as the party seeks to end dual mandates.
Party president Gerry Adams said each will stand down from the Northern Ireland Assembly where new representatives can be put in their place without further elections.
Mr Adams added that his party would continue to refuse to sit in Westminster, but wanted to avoid creating a string of electoral contests by resigning all five of its parliamentary seats.