BELFAST, Northern Ireland (AP) – Hard-liners triumphed in elections for Northern Ireland’s seats in the British parliament, as the Nobel Peace laureate who tried to steer Protestants toward compromise suffered a crushing defeat.

The opposite poles of Northern Ireland politics – the British Protestants of the Democratic Unionists, and the Irish Catholics of Sinn Fein – won the lion’s share of 18 seats in this divided corner of the United Kingdom. Analysts agreed the results reflected each side’s desire to be represented by tough negotiators.

The biggest casualty from Thursday’s vote was Ulster Unionist Party leader David Trimble, who spent years struggling to sustain Protestant support for Northern Ireland’s 1998 peace accord. Its central achievement, a Catholic-Protestant administration led by Trimble, collapsed in 2002 amid chronic arguments over Irish Republican Army activity.

His Democratic Unionist challenger, David Simpson, trounced Trimble by 16,679 votes to 11,381, ending his 15-year hold on a mostly Protestant district southwest of Belfast. His loss raised the likelihood that Trimble, 60, would resign or be forced out as Ulster Unionist leader, a position he’s held since 1995.

“There is no greater honor that anyone can have than to sit in the British House of Commons and to represent their constituents there. I am proud of our record,” said Trimble, his voice shaking and his face flushed as Protestant youths banged drums in celebration outside the election center.

The hard-line Democratic Unionists won nine seats, up four from the last parliamentary election in 2001, when the Ulster Unionists were still on top with six.

This time, the Ulster Unionists retained only a single seat, its worst result since Northern Ireland’s creation as a predominantly Protestant state in 1921.

Trimble, 60, who has survived several party splits and leadership challenges, said he would consult party colleagues before deciding whether to stay or go as party leader.

Democratic Unionist leader Ian Paisley, who easily retained the seat north of Belfast he’s held since 1970, said the result demonstrated that Protestants would not cut any more open-ended deals with Sinn Fein, the IRA-linked party.

Democratic Unionist deputy leader Peter Robinson, who cruised to victory in Protestant east Belfast, called the result “a watershed” and said the Ulster Unionists should accept their decline as irreversible.

“I believe that in the years to come, people will look back on this time and see this as being the decisive election,” said Robinson, 56, heir apparent to the 79-year-old Paisley.

Robinson criticized Sinn Fein leaders as people “who seek to lead a double life, who seek to be terrorists and criminals on one occasion, and to be politicians on another.”

But Sinn Fein made its own gains in predominantly Catholic areas, winning five seats in direct competition with the moderate Social Democratic and Labour Party. The party once represented most Catholics but was knocked into second place in 2001 – and was considered lucky to retain three seats Friday.

Social Democratic and Labour Party leader Mark Durkan easily won the seat in Londonderry, Northern Ireland’s predominantly Catholic second-largest city. Protestant politicians in the city said their supporters had backed Durkan in order to keep out the Sinn Fein candidate, Mitchel McLaughlin.

The SDLP also took advantage of a badly split Protestant vote to win in south Belfast, the most peaceful and prosperous side of the capital. Alisdair McDonnell became the first Catholic to represent the district in Northern Ireland history.

“The electorate has sent us a very clear message – that tribal politics is not the only way forward in Northern Ireland,” said McDonnell, a doctor who is a vocal critic of the Sinn Fein-IRA movement.

AP-ES-05-06-05 2157EDT