Dafydd Wigley led Plaid Cymru from 1981 - 84 and 1991 - 2000
Former Plaid Cymru leader Dafydd Wigley claims attempts to have members of his party elevated to the House of Lords are being snubbed.
Mr Wigley is one of three people nominated a year ago by Plaid as candidates to sit as peers.
He has accused the UK government of failing to recognise those nominations
However, the UK Cabinet Office says Plaid has not followed "correct procedures" for political appointments to the Lords.
Mr Wigley, who is the party's honorary president, said he would now be meeting Plaid's leadership to discuss the matter.
He told BBC Radio Wales that he and the other nominees, the former AM Janet Davies and the party's economic adviser, Eurfyl ap Gwilym, had been left "in limbo".
"Our names were elected a year ago by our national council," he said.
"Since then it seems to have run dry. As far as we can make out there has been a block in Downing Street.
"We just want to know where we stand, because this can't go on forever and a day."
The former MP and AM for Caernarfon said the party had been originally advised by the UK government's chief whip to submit names to be considered for political peerages.
However, the Cabinet Office questioned the approach taken by the party.
"We cannot comment on individual cases, but Plaid Cymru did not follow the correct procedure," said a spokesperson.
"They made unsolicited nominations.
"The procedure is that from time to time the prime minister makes political appointments to the Lords by seeking nominations from party leaders."
But Plaid's parliamentary leader Elfyn Llwyd also disputed the Cabinet Office's position.
"If we have not followed the correct procedure, why was I not told that in January (2008)," asked the MP for Meirionnydd Nant Conwy.
"It is clear that the Conservative and Liberal Democrat leaders have been asked to make nominations by Gordon Brown, but no such invitation has been extended to Plaid Cymru or the SNP for that matter.
"I know that members of the Cabinet have backed our nominations and the government chief whip had no problem.
"It seems this is a matter of pure prejudice on the Prime Minister's part against a perfectly sensible political party."
Mr Llwyd said he would be personally writing to Gordon Brown to ask for a meeting on the issue.
Plaid has one member of the Lords, Welsh assembly Presiding Officer Dafydd Elis Thomas, although he was not nominated by the party.