DUP deputy leader Nigel Dodds is to stand down as Assembly member for North Belfast but will hold on to his Westminster seat, the party has announced.
The North Belfast MP is to give up his Assembly seat within days as part of the DUP leader Peter Robinson's commitment to phase out the Stormont-Westminster dual mandate system. The DUP said the party was in the process of choosing his successor.
The party now has just two members who hold seats both in the Assembly and in the House of Commons, East Derry representative Gregory Campbell and East Antrim MP and MLA Sammy Wilson, who is the North's minister for finance.
DUP MPs Jeffrey Donaldson, Ian Paisley jnr, the Rev William McCrea, David Simpson and Jim Shannon have also given up their Stormont seats.
Mr Campbell is expected to opt for Westminster shortly while Mr Wilson may remain in place for some time to deal with imminent cuts to the Northern Executive's budget.
Five of Sinn Féin's MLAs are also MPs - party leader Gerry Adams, Deputy First Minister Martin McGuinness, agriculture minister Michelle Gildernew, regional development minister Conor Murphy and West Tyrone representative Pat Doherty.
Sinn Féin does not take its seats in the House of Commons. A spokesman said that Sinn Féin was signed up to ending the dual mandate by 2015 and was "working to that goal".
Former SDLP leader Mark Durkan, an MP and MLA, has said he will not stand for the Assembly in his Foyle constituency in May next year to concentrate on his Westminster work.
Party leader Margaret Ritchie has stated that she believes as leader she should hold on to her Stormont and Westminster seats in South Down, but that she favoured a cross-party approach to ending dual mandate.
The SDLP MP and MLA Dr Alasdair McDonnell said he intended to run for Stormont next May while holding on to his House of Commons seat. The SDLP was working to get rid of dual mandate but in the meantime he believed he could carry out both functions.
Naomi Long of Alliance - who took DUP leader Peter Robinson's Westminster seat in the May general election - has already stood down as an MLA for the constituency.
