The spokesman, Richard Ottoway, who attended the all-party launch, said: "These are questions Jeffrey has got to face up to and I am sure he will."
Lord Archer reinforced his campaign to be adopted as the Tory candidate in a Centre for Policy Studies pamphlet, "A Better Deal for London", claiming the capital needed a mayor who could "make a difference". He said Londoners "pay more and get less", contributing pounds 12bn more in taxes per year than they get in government expenditure.
The Government is confident of a big "yes" vote in the London referendum on 7 May, but the Cabinet devoted part of its weekly meeting to discussing the threat of big Labour losses in the local elections on the same day.
The Scottish elections next year are causing more concern to ministers as a test of Labour's popularity in its heartlands in the run-up to the next general election. A third special adviser is to be appointed by Donald Dewar to help the Secretary of State for Scotland spearhead Labour's fight back against the Scottish National Party for elections to the new parliament.
The Prime Minister's spokesman said: "The Scottish elections are going to be hugely important. There have been discussions about putting together a long-term strategy that Donald Dewar will be involved in."