Northern Ireland’s only unionist Remainer MP has said she will not contest the general election.
Lady Sylvia Hermon announced that she would not be defending the North Down seat she took in 2001.
She was under pressure from a Democratic Unionist rival who cut her majority to 1,208 in the last poll in 2017.
She said: “Serving as an MP is a tremendous privilege and I remain profoundly grateful to all those who placed their trust and confidence in me in the last five general elections.
“It has undoubtedly been the greatest honour of my life to serve the people of North Down as their Member of Parliament since 2001, and so it is with enormous sadness that I have decided not to contest the next General Election in December.”
Her decision comes days after Sinn Fein and the SDLP announced they would endorse her as the remain candidate in the constituency.
Hermon called this a “particularly difficult decision”, but concluded “it is the right decision for my family and me at this time”.
On Twitter, the deputy leader of the Alliance Party Stephen Farry said: “Sylvia Hermon has been a great servant to North Down and Northern Ireland over the past years.
“In particular, she has stood up against a reckless Brexit and for the Good Friday Agreement. We wish her well for her next steps.”
Hermon represented one of Northern Ireland’s most affluent and staunchly unionist constituencies, made up largely of Belfast commuter towns and coastal villages.
Hermon apologised for any disappointment caused to constituents who had urged her to stand again for re-election and thanked volunteers in previous election bids.
In 2005, she was the only Ulster Unionist MP to retain her seat after the party suffered catastrophe in the Westminster election.
She has been an independent since then and an assiduous worker on the Northern Ireland Affairs Committee, where she has scrutinised official performance with a keen eye for detail.
She recently called for a clear guarantee on the new Brexit deal.
Lady Sylvia has highlighted unionist anger at prime minister Boris Johnson’s proposed agreement with the EU over its perceived implications for the constitutional status of Northern Ireland.