Image caption Mr McDonnell was first elected to the South Belfast seat in 2005

The SDLP leader and South Belfast MP Alasdair McDonnell has said he will be giving up his assembly seat to concentrate on remaining as an MP at Westminster.

He retained his seat in South Belfast with 9,560 votes.

Mr McDonnell was first elected to the seat in 2005.

The South Belfast MP told the BBC's Sunday Politics Show he would talk to party colleagues and "set processes in train" to find a replacement.

"I will be talking to the party about the process of moving now that I have secured the Westminster seat for the third time and that's a major achievement," he said.

"South Belfast is still a unionist majority constituency."

The SDLP also held onto its Westminster seats in Foyle and South Down.

The DUP won the largest number of seats in the general election securing eight.

Sinn Féin won four seats, the UUP two and Lady Sylvia Hermon retained her seat in North Down as an independent.

In 2014, the Northern Ireland Office passed an act banning MPs from double-jobbing.

The section of the law banning double-jobbing comes into force "the first day after this act is passed on which the Northern Ireland Assembly is dissolved".

Barring an early election, the next Stormont dissolution should be in March 2016, ahead of assembly elections in May 2016.