Northern Ireland First Minister Peter Robinson will stand again for his Westminster seat in the forthcoming general election.
However, the DUP leader pledged to end "double-jobbing" among colleagues who will give up seats in the Assembly if they are elected to the House of Commons.
The East Belfast MP said the prospect of a hung parliament meant it was important the party leader remained an MP as he launched the party's general election campaign in Belfast.
"While personally I made no secret of the fact that I would have been content to concentrate on the Assembly, I understand the access that comes with being a member of parliament is important for the leader of unionism, whoever that is," he said.
He said the increased stability at Stormont, as well as the strength of the Assembly team, allowed the party to take these steps.
He added they had ensured local people would be in charge of a justice department while the independence of Chief Constable Matt Baggott and the judiciary would be upheld and maintained.
The party's election slogan will be "Let's Keep Northern Ireland Moving Forward".
Mr Robinson accused the Ulster Unionist Party (UUP), which opposes the transfer of policing and justice powers from London to Belfast, of "play-acting at its worst".
He also said Jim Allister's Traditional Unionist Voice (TUV), which opposes power-sharing with Sinn Fein, was dividing unionism further and playing into the hands of republicans.
Mr Robinson said life in Northern Ireland was unrecognisable from what it was a generation ago.