Former first secretary Alun Michael has attacked the Assembly's presiding officer claiming his "disgraceful" actions "triggered" his resignation.

Mr Michael said Lord Dafydd Elis-Thomas's actions persuaded him not to fight on.

"In the event that triggered it," said Mr Michael.

"It became quite clear that he was changing the rules in a way that would suit Plaid Cymru and give considerable difficulty to the members of the Labour group.

"What he had previously said he would do was to take the nominations for a new first secretary - which doesn't necessarily mean a different first secretary - first thing on Thursday morning.

"As there had been a suggestion of further no confidence votes he indicated that it would be considered in the way of normal business next Tuesday.

"By saying he would take it straight away it would mean that if I went ahead in facing them down and saying 'go on, do it again' the members of my group would be faced immediately with a series of further votes without the opportunity to reflect or consult the wider party," he added.

Mr Michael said he thought it was time to cut through the "dictatorship" from the smaller parties and that he wanted to allow the Labour Party to take the decision.

"I challenge Dafydd Elis Thomas's decision. I think it is quite wrong," said Mr Michael.

"I think it is quite disgraceful and I think it has the potential to bring the Assembly into disrepute for not dealing with things properly.

'Preserve integrity'

"I felt that what I had to do was to try to protect the interests of the Labour Party and the interests of the people of Wales by trying to preserve the integrity of the Assembly.

"In some ways I resented having to take that approach because I think there is a duty on the presiding officer and on the smaller parties to have regard to the integrity and reputation of the Assembly.

"It is now quite clear that they don't have sufficient regard for it," he added.

Lord Elis-Thomas said: "As Presiding Officer I am accountable to the whole Assembly.

"All my decisions are taken within the standing orders of the Assembly which were approved by Alun Michael when he was Secretary of State for Wales."