British MP Jeffrey Donaldson on Monday announced his candidacy to lead Northern Ireland's unionist DUP party, after internal divisions forced leader Edwin Poots to resign.
"It is with optimism for the future and recognition of the challenges facing Northern Ireland that today I put my name forward for the leadership of the Democratic Unionist Party," Mr Donaldson said.
"I believe that if I am elected leader, I can put the Democratic Unionist Party on the path to victory at next year's election."
He had indicated that he would give up his position as a member of Parliament at Westminster if he won the nomination and became head of the Northern Ireland government.
Candidates for the DUP position have until noon on Tuesday to apply, and Mr Donaldson is the only person in the running so far.
Mr Poots, who became leader of the ultra-conservative party only three weeks ago, announced his resignation last week after a rebellion similar to the one that brought down his predecessor, Arlene Foster.
Ms Foster was accused of allowing Customs controls to be put in place for goods coming from mainland Britain, creating a border.
Mr Poots was brought down by anger in his camp after last-minute concessions to Sinn Fein over a new power-sharing government, as provided for in the 1998 Good Friday agreement.
That deal ended the Troubles, the 30-year conflict between unionists and republicans.
Before being forced out, Mr Poots appointed loyalist Paul Givan as the province's First Minister, a role he assumed on Thursday but will be under pressure to relinquish when a DUP leader is elected.
Tension has been rising in the UK province of about1.9 million people.
Unionists are upset about the Northern Irish protocol negotiated as part of Brexit, which they say threatens the province's place in the UK.
Aimed at avoiding a physical border between the Republic of Ireland and the North, the agreement keeps the province in the European single market and Customs union for goods.
The Northern Ireland protocol is the "number one issue", Mr Donaldson said on Monday.
He promised that if elected, he would "ensure that the government doesn't just listen, but recognises the need to take decisive action.
"Now, more than ever, we need to unite in the face of the threats posed to Northern Ireland by the protocol," he said.
Mr Givan has promised that Mr Donaldson would have his support if he was confirmed as leader.
