Plaid's Dafydd Elis Thomas is staying away, defying his party's three line whip, sharing "full and frank exchanges" with his group and expecting the sanctions and the trouble that has been a long time coming.

BBC: 'No conniving' and 'no conspiracy'

It added that a number of these votes were subject to the UUP three-line whip.

BBC: Weir to fight suspension

Mr Pritchard told BBC Radio 4's Today programme he was willing to defy a three-line whip if necessary.

BBC: EU referendum: MPs told to vote against Monday's motion