Tory consensus faces a fatal blow today as grass-roots activists from across Britain unite for the first national conference of the People's Assembly Against Austerity.

Hundreds of trade unionists, community activists, students and pensioners are to arrive in London to unleash a wave of anti-cuts action that organisers hope will spark an unprecedented moment of political change.

That action includes national demonstrations on June 21 and October 18, plans for which will be revealed at the meeting.

The vital gathering comes as Chancellor George Osborne sharpens his knife ahead of Wednesday's Budget, when he is expected to announce yet more crippling public-sector cuts.

People's Assembly national secretary Sam Fairbairn said the meeting has been made only more significant by the deaths of "tireless campaigners" Bob Crow and Tony Benn this week.

He told the Star: "The best way we can honour their legacy is by picking up our campaign and doubling our efforts to put a stop to these draconian austerity measures forcing millions towards poverty."

In a warning to Labour, Mr Fairbairn also promised that the movement would remain a "thorn in the side" of any austerity government.

He has travelled across Britain alongside journalist Owen Jones, comedians Francesca Martinez and Mark Steel and other high-profile backers to launch local groups since the People's Assembly founding conference in March 2013.

Now, from Brighton to Berwick and from Carmarthen to Cambridge, action is being organised by over 70 groups.

More than 200 people fed-up with Tory lies turned out just for the launch of the latest branch in Coventry two weeks ago.

Branch chairman Tony Conway said it was the potential of the People's Assembly that stirred up the hope that created the biggest political meeting in the city for years.

"It's been a catalyst to bring people together who would not have done so if the People's Assembly had not existed," he said.

"Some of the sectarian lines that existed have been broken down and made people who have their own local campaigns recognise they are part of a bigger struggle."