DUP Agriculture Minister Edwin Poots is to replace Christopher Stalford as the party’s MLA in South Belfast.
Mr Stalford, a 39-year-old father of four, died suddenly last month.
Mr Poots is currently an MLA in Lagan Valley.
Read more: Christopher Stalford: MLAs pay tribute at Stormont Assembly
Announcing the switch, DUP leader Sir Jeffrey Donaldson said: “We are bound by the rules of the Assembly which requires us to appoint a replacement within seven days of a vacancy arising.
“Edwin (Poots) has been selected to be the member for South Belfast, to continue following in Christopher’s footsteps in representing the people of this constituency.
“This almost concludes our selection process for the Assembly elections.
“We just now need to select candidates in Lagan Valley and then we will be in a position to ratify all of our candidates.”
Edwin Poots said he had been asked to become MLA for South Belfast by the family of Christopher Stalford.
He said: “I stand here with a lot of regret, we have lost a good colleague and friend in Christopher Stalford.
“We are standing here of necessity, more than anything else.
“Last week the (Stalford) family spoke to me and asked me would I consider taking on the role of MLA for South Belfast and it was on that basis that the party asked me to take on this responsibility.
“I have a hard act to follow.
“It is also with regret that I leave the constituency of Lagan Valley.
“Sometimes you have to make hard decisions and that is the decision I have made and I believe it is a decision that will bring some degree of comfort to the family that they have someone with the same values as Christopher representing this constituency.”
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