McGuinness to step down as MP

Mr McGuinness is MP for Mid-Ulster - his resignation will now result in a by-election in the constituency.

Four MLAs are also leaving their posts as the party moves to put an end to 'double-jobbing', it was revealed on Monday.

Pat Doherty will leave his position as West Tyrone MLA, Paul Maskey will vacate his West Belfast position, Michelle Gildernew will be replaced in the Fermanagh and South Tyrone constituency and in Newry and Armagh, Conor Murphy will leave his post.

The new MLAs will be in place by the beginning of next month.

Party president Gerry Adams said 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.

Mr Adams said: "The key thing to be said about this issue is that other parties are talking about ending dual mandate, Sinn Fein has ended dual mandate."

However, Alliance Councillor Conrad Dixon claimed the contribution of Sinn Féin MPs' at Westminster will remain unchanged due to their policy of abstentionism.

Cllr Dixon said: "While I welcome any other party ending double jobbing between the Assembly and Westminster, the fact is they do not take their seats so there is not much for them to concentrate on.

"It is good to see that they are belatedly following my Alliance colleague Naomi Long's lead in ending double jobbing, even though she was two years ahead of them."

The Craigavon representative described Sinn Féin as "voiceless" at Westminster due to the party's refusal to take their seats.