Plaid Cymru's former president Dafydd Wigley has said he "cannot foresee circumstances" which would lead him to stand in the 2007 assembly elections.
Dafydd Wigley said the reasons for him standing down had not changed
His comment comes as he is nominated as the party's honorary president - the position held by former party leader Gwynfor Evans until his death in April.
Mr Wigley said the reasons for standing down as an AM in 2003 had not changed.
He said "I am not on the (party's) list of candidates. I have not put my name forward. I have no plans to do so."
Mr Wigley was speaking as it was announced that he was being put forward for the party's titular role of honorary president, a nomination widely expected to be approved at the party's conference this weekend.
The title of honorary president does not bring with it any formal responsibilities, but it will give Mr Wigley, who was MP for Caernarfon for 27 years, added status and influence within Plaid Cymru.
Mr Wigley has previously said he would be "duty bound" to consider a return to the assembly if the party wished it.
But speaking about the nomination for honorary president, he said he was keen to play his part in securing the party's success but also played down speculation that he may stand for a seat in the 2007 assembly elections.
Born Derby 1 April 1943
Educated Manchester University; industrial economist
Married Elinor Bennett
Caernarfon MP 1974-2001 and AM 1999-2003
Sponsored the Disabled Persons Act of 1981
Plaid Cymru president 1981-4 and 1991-2000
He told BBC Radio Wales: "I can't foresee circumstances in which I'm going to stand.
"We don't even know for certain what will be the boundaries of the constituencies in Gwynedd, neither do we know the system for the regional list for the national assembly.
"Until those questions are cleared, it's impossible for the party - not in my context but in anybody's context - to move forward to make those decisions."
Constituency boundary changes in Gwynedd might see the Caernarfon constituency he represented as both an MP and an AM re-drawn and called Arfon.
Last week, the party's deputy assembly leader Rhodri Glyn Thomas called on Mr Wigley to end speculation about his political ambitions.
Mr Thomas told BBC Wales: "The continuing saga of will he, won't he, where's he going to stand... I don't think that does any good to the party at all."
Gwynfor Evans, Plaid's first MP, died in April, aged 92
Mr Wigley added: "What is important is that the party, instead of arguing about who is doing what in various jobs, pulls together to project to the people of Wales an alternative set of policies that can produce better government for Wales.
"That is my ambition, not an ambition to be back to where I was two years ago or 20 years ago."
Mr Wigley said he would be "honoured" to fill the honorary party post left vacant after the death of Gwynfor Evans, Plaid Cymru's first MP, in April this year at age 92.
He said: "(Gwynfor Evans) was seen a person who united the party.
"I would hope that I could play some little part in the same sort of process, bringing things together and project Plaid Cymru forward. I hope it will provide a base that will allow me to assist the party."