Plaid Cymru has suffered a huge election blow losing the seat previously held by party leader Ieuan Wyn Jones.

Labour took the Ynys Mon seat with a majority of 800 polling 35 per cent of the total vote.

Plaid came in second with 11,106 votes. In third place were the Conservatives with 7,653.

In 1997, Jones won the seat with a 2,481 majority over the Labour candidate. He had held it since 1987 after gaining it from the Conservatives.

The Plaid leader was clearly distressed as the official declaration approached in Ynys Mon at half past midnight. Whilst preparing for an interview, he was privately informed of the anticipated result and responded by leaving the building.

"The loss of Ynys Mon is a disappointment. This has always been an exceptionally volatile seat and we clearly underestimated the large personal vote enjoyed by Ieuan Wyn Jones," said Plaid's chief executive Karl Davies.

However, the nationalists looked on the bright side, with the "substantial boost" of victory in Carmarthen East and Dinefwr.

"As we have predicted throughout this campaign, we have also secured our highest ever share of the popular vote in a Westminster election. We have substantially increased our level of support throughout Wales and confirms our position as the main challenger to Labour in its heartlands," said Davies.

Glenys Kinnock said the Anglesey result was a "ringing endorsement" of Labour's candidate, Albert Owen.

"This result also shows that the nationalists under Ieuan Wyn Jones have made a critical strategic error in this election. They have taken their seats for granted in a failed attempt to target Labour's heartland," added Kinnock.

The Welsh Liberal Democrats described the results for them as a step forward. They took 13.8 per cent of the vote in Wales, leaving them in fourth place behind Labour, the Conservatives and Plaid Cymru.

Mark Soady, chair of the Welsh Lib Dem campaign, said the results showed "the benefits to working with another party in the partnership government in the National Assembly."

"It was a bad night for Plaid Cymru. They lost their leader's seat and more than half the share of the vote they won at the assembly elections. Their challenge to Labour in the valleys evaporated," he added.

Reflecting on the poor results of the Welsh Conservatives, a party spokesman said: "'We are extremely disappointed with the result in Wales, but having said that we cut down the Labour majority in many seats and came within a whisker of winning some."