The Ulster Unionist's disciplinary panel meets today to decide the fate of two Northern Ireland assembly members who voted against their leader David Trimble in his battle for position of first minister.

North Down assembly member Peter Weir and East Londonderry MLA Pauline Armitage from could face expulsion after defying the party executive and voting with the anti-agreement Democratic Unionist party.

Their rebellion denied the crossbench support needed by Trimble and deputy first minister Mark Durkan in the first vote to form a Northern Ireland executive, precipitating a political crisis in the Stormont institutions despite overwhelming support from the majority of the assembly as a whole.

This is the first time that Armitage has faced the panel after 30 years as a party member, although this is Weir's second appearance.

Earlier this year, he was suspended from the Ulster Unionists for three months after defying the party whip at a number of Stormont votes and the rebel MLA has threatened a court challenge to the panel's membership, arguing that he will be "tried again by the same jury".

Both members will have the right to appeal any decision that the panel reaches.