Plaid Cymru withdraws whip from ex-leader Lord Dafydd Elis-Thomas
Plaid Cymru has withdrawn the whip from its former leader, Lord Dafydd Elis-Thomas.
The AM for Dwyfor Meirionnydd said he had a "valid reason" for not attending the controversial vote of no-confidence over Wales' health minister Lesley Griffiths.
He criticised his party's stance, saying the debate "puts prejudice before evidence".
But a Plaid spokesman said there was no "satisfactory reason" for his absence.
The whip has temporarily been withdrawn.
Lord Elis-Thomas has given a brief statement to S4C's CF99 political programme.
"I will argue (in the disciplinary hearing) that I had a valid reason for my absence," he said.
Lord Elis-Thomas stayed away from Cardiff Bay to preside over a graduation ceremony at Bangor University, where he is chancellor.
A party spokesman said: "A member of the Plaid Cymru group in the National Assembly did not attend today's vote in the Assembly and did not provide a satisfactory reason for his absence.
"As a result, the whip has been temporarily withdrawn from Dafydd Elis-Thomas without prejudice pending an internal process."
Before the vote, Lord Elis-Thomas told BBC Wales that on the basis evidence he had seen he could see "no reason to pursue this vote of no confidence."
He added: "Plaid has put itself in a position of being the supporting cast to a play which was produced by the Welsh Conservatives, and that gets under my skin."
The Conservatives, Plaid Cymru and the Liberal Democrats supported a no-confidence motion on Wednesday at the last plenary session before the long summer recess.
Ms Griffiths survived the vote in a row about a controversial report into reorganising hospital services.
It was defeated 29 votes to 28.
As the assembly's 60 seats are evenly split between the government and the opposition, the motion would have needed a Labour rebellion to get it through the Senedd.
Lord Elis-Thomas was presiding officer of the Welsh assembly for 12 years.
He was Plaid leader between 1984 and 1991 and has been an assembly member since 1999, previously serving as an MP since 1974.
In January, the peer was nominated by his local party to run again for the leadership but came last in the first round of voting.