Ken Livingstone's former advisor Lee Jasper returns to head May Day protest

Thousands of activists are set to descend on central London to demonstrate against the coalition Government's austerity measures on Sunday as part of the annual May Day protest.

It will mark the return to front-line campaigning of Lee Jasper, who resigned as senior policy adviser on equalities at City Hall in March 2008 after allegations over his conduct.

Billed as the "next stage in the battle against cuts and job losses", students, pensioners and trade unionists will gather in Trafalgar Square to increase pressure on the Government as part of the "fight to save jobs and services".

Mr Jasper will speak on behalf of his organisation Black Activists Rising Against the Cuts alongside veteran activist Tony Benn and Sarah Veale of the TUC.

His former boss Ken Livingstone has pulled out because of "family commitments".

Jasper, 52, was forced to resign after leaked emails revealed he offered to "honey glaze" Karen Chouhan, the married director of two projects being funded with public money.

He also failed to declare his friendship with Ms Chouhan, as City Hall rules require, before recommending that her organisation be funded.

Activists will gather at midday at Clerkenwell Green before marching to Trafalgar Square for 1pm.

Organisers said the event, which has been held every year for more than a century, was a "unique bringing together of trade unionists, workers, pensioners, anti-globalisation organisations, students, political bodies and many others in a show of working class unity".