London, Sep 9 (DPA) British Prime Minister Tony Blair - who has confirmed he will step down in the coming year - warned his Labour Party against returning to the bad old days of party infighting.

During a speech to centre-left think tank Progress, Blair also called for an immediate end to personal attacks "by anybody on anyone."

But the row over who was to succeed Blair as prime minister continued.

In the latest opinion poll, one in two Britons said they wanted Blair to leave office by the end of the year. Only 21 percent wanted him to stay on as prime minister.

Blair was speaking in public for the first time Saturday since his announcement Thursday that he would step down within 12 months.

However, his announcement did not, as he had hoped, quell the debate within the party about how long he would still remain in office.

Massive criticism of both Blair and his most likely successor Chancellor of the Exchequer Gordon Brown continued into the weekend.

The most acute attack on the current chancellor came from former home secretary Charles Clarke, a political heavyweight in the party.

Clarke described Brown in The Daily Telegraph as a "control freak", who interfered in everything and who was unable to work with others.

Blair called for party members to stop the attacks, saying they harked back to Labour's time in opposition in the 1980s when the party was dogged by bitter infighting. He said the events of the previous weeks were "irredeemably old-fashioned".

The British press speculated that Blair would hold out until May 2007, which would mark his 10th anniversary in office.