A Welsh Labour MP has warned Tony Blair that the saga of his retirement plans is "bleeding the Labour Party at its heart".
Mr Touhig says Gordon Brown should lead the Labour Party
Don Touhig, the Islwyn MP sacked from the government earlier this year, said Mr Blair should confirm that he has a timetable in mind for his departure.
He said Labour's chances in next year's Welsh assembly election have been damaged by the leadership uncertainty.
Mr Touhig is a former Wales Office and defence minister.
He is also a prominent supporter of the chancellor, Gordon Brown.
He told the website epolitix.com: "We need to resolve this leadership issue sooner rather than later.
"The party wants an indication that a timetable is in mind, that there are positive discussions going on between Tony and Gordon because, whoever else might challenge, the overwhelming view of the party and the public is that Gordon should be the next leader."
He added that the party needed "reassurance that things are moving forward" because a prime minister's powers began to "seep away" once an administration's "sell-by date" had been announced.
Mr Touhig said he wanted Tony Blair to go out on a high because he was owed a great deal by both "the party and the country".
However, he added: "But he will not be best served if this extended departure goes on and on bleeding the Labour Party at its heart."
Mr Blair should 'go out on a high' says Mr Touhig
Mr Touhig warned that the wrangling over the leadership could damage Labour's electoral chances as it gave the impression that Labour was divided.
He said: "Next year we have assembly elections in Wales, local elections in England and parliamentary elections in Scotland and I am very concerned that we will be punished in those elections because of this uncertainty over the leadership."
Mr Touhig said he believed Mr Brown would not be challenged for the leadership by Home Secretary, John Reid, and he said he was unsure what support Mr Reid would enjoy from the parliamentary party if he was to stand.
He said: "I think John probably has enough on his plate at the Home Office at the moment, which is not in a good state."