Tom Elliott is to quit as Ulster Unionist leader after accusing party critics of not giving him a chance.
He dramatically announced tonight that he will not be seeking re-election at the party's annual meeting later this month.
Elliott, a member of the Northern Ireland Assembly who took over the leadership in the summer of 2010, claimed: "I am well aware that some people have not given me a fair opportunity at developing and progressing many initiatives.
"Some of this obstruction and hostility began immediately following my election as leader and has been relentless since then. However I accept that is part and parcel of politics."
His leadership has been under pressure since the party's dismal performance in the Assembly elections in May last year - which followed an equally disastrous General Election when the party failed to win a single seat.
In a statement tonight, Elliott said: "Following my election as leader I set about improving internal party structures, since then I have amended the party rules, including discipline; significantly increased internal party communications; negotiated a move for new party headquarters and strengthened our staff structure.
"I have also been successful in leading the political field by making a start to reviewing the government structures and reducing the over-governance of Northern Ireland."
Elliott took over the leadership from Sir Reg Empey in August 2010. He will remain a member of the Assembly for Fermanagh-South Tyrone.
The election of the new leader will take place on March 31.
Basil McCrea and Danny Kennedy are likely emerge as some of the front-runners for the job.
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