Blair's ally Lord Falconer may sue Brown in row over six-figure pension

Gordon Brown faces being sued by one of Tony Blair's closest friends, it emerged last night.

Lord Falconer is planning a legal challenge against the Prime Minister in an attempt to double his taxpayer-funded pension.

The dispute could become especially bitter because the former Lord Chancellor is a possible ringleader in a Blairite rebellion against Mr Brown's premiership.

Last month the peer, who is Mr Blair's former flatmate, criticised Mr Brown's decision not to call a general election and suggested he lacked vision.

Lord Falconer, who left the Government in June at the same time as Mr Blair, is said to be outraged that his annual pension entitlement is £52,193 - half the deal enjoyed by his predecessors.

Mr Brown, acting in line with a precedent set by Mr Blair four years ago, ruled out a higher figure.

In June 2003, amid a row over ministerial salaries, Lord Falconer did not take a £232,900-a-year package on offer, but opted for the standard £104,386 deal paid to cabinet ministers based in the House of Lords.

He had been entitled to an annual salary and pension that exceeded any other Cabinet minister, including the Prime Minister.

This was designed to reflect the fact he had given up a private legal earnings of more than £500,000 a year. On leaving office, Lord Chancellors are banned from returning to practise at the bar to avoid them appearing in cases with judges they have appointed.

Private talks between Mr Brown and Lord Falconer about the settlement have "ground totally to a halt".

Last night, a Cabinet Office spokesman refused to comment on individual cases but added: "The position remains as set out by the former Prime Minister in a statement to Parliament in June 2003."

Lord Falconer refused to comment nor would a Downing Street spokesman.

Allies of Mr Blair have privately expressed doubts over the direction of the Government since Mr Brown took over.

At the height of fevered speculation over a possible election last month, Lord Falconer infuriated Downing Street by going public with his criticism.

He warned that a change of leadership at the top was not enough to renew New Labour adding: "If we rely on experience and our ability to handle crises and do not set out our vision for the UK, then we will offer drift not leadership."

It triggered a flurry of other veiled criticism from Blairites, including Cabinet Minister John Hutton.