Dafydd Elis Thomas is the only Plaid party member to sit as a peer

Plaid had always rejected the policy of creating its own peers because it wanted the Lords to be fully elected.

But Dafydd Elis-Thomas said his party's vote for policy change would ensure it is better represented at Westminster.

The process of nominating and selecting suitable candidates to go to the Lords will now begin.

A meeting to decide the matter will be held in January.

Plaid parliamentary leader Elfyn Llwyd had also argued that new powers for the Welsh assembly, which are ratified by Parliament, meant the party needed peers.

Members voted on the policy change at a meeting of its national council in Aberystwyth on Saturday.

At Plaid's conference in September representatives agreed to review the policy after Mr Llwyd argued that peers were required to ensure planned legislation for Wales was not blocked at Westminster.

The members were also required to reflect the views of the people of Wales in the Upper Chamber, he said.

The Welsh assembly's new powers under the Government of Wales act allows it to make its own laws in devolved areas, with the permission of Parliament.

We have seen with the cash for honours scandal and all the problems that this has induced that the Lords is not a very democratic institution Bethan Jenkins AM

Mr Llwyd warned that many in the House of Lords might want to block such permission, known as Orders in Council.

Lord Elis-Thomas, the only Plaid party member to sit as a peer, has sat as a cross bencher, not as a party appointee, since 1992.

Speaking after the vote, he said: "I think it's long overdue because we have not been represented as a party and as a point of view in the politics of Wales in the second chamber of the UK, especially now when legislation, the orders that empower the assembly, are being made through Westminster."

But there was some opposition within the party ranks.

Reform

Bethan Jenkins AM argued the Lords needed to be completely reformed before Plaid representatives were sent there.

"We have seen with the cash for honours scandal and all the problems that this has induced that the Lords is not a very democratic institution," she said.

"We should be utilising our resources in other ways.

"We should be looking forward to the referendum in 2011 or before - that is where we need to put our best people."

Plaid last discussed this issue in 1999 when a vote went against the motion.

This means that the issues raised by MEP Jilll Evans, who also chairs CND Cymru, could be revisited in the future.

She believes the proposed 5,000-job centre is inconsistent with the spirit of the party's defence policy.

A party spokesman denied that they were avoiding the issue.