Doug Beattie resigned from the Ulster Unionist Party on Sunday and will sit as an independent MLA.

In a letter to party leader Jon Burrows, Beattie stated that his membership was no longer tenable. He cited a marked deterioration in relations within the party over the past two years.

Beattie said he had persuaded Burrows to join the UUP and later regretted the decision. He claimed an insidious element within the party had been briefing against him on selections and other issues.

Beattie said the final matter involved the party reopening a disciplinary case over tweets from four years ago.

A UUP spokesperson said the party management board had met on Thursday and agreed a course of action regarding concerns about Beattie's conduct and judgement. The spokesperson said the party did not accept Beattie's characterisation of recent events.

Beattie was first elected to the Northern Ireland Assembly in 2016 for Upper Bann. He had previously served as party leader from 2021 to 2024.

He had been facing deselection by his constituency association ahead of the next assembly election.