Actor Ricky Tomlinson will address a fringe meeting of the Labour Party conference this week as he campaigns to overturn a 39-year-old conviction for picketing offences.

The Royle Family star was one of 24 building workers put on trial in Shrewsbury in 1973 after being charged under the 1875 Conspiracy Act.

Six of the pickets were imprisoned, including Tomlinson who served 16 months of a two year sentence for conspiracy to intimidate.

Supporters say the "Shrewsbury 24" were victims of a "government plot to intimidate trade union members".

The Shrewsbury 24 Campaign claims a Hillsborough-style cover up is preventing cabinet papers on the matter from being released.

It has launched an e-petition on the Number 10 website asking for "full disclosure of all Government documents relating to the 1972 building workers strike and the conspiracy trials at Shrewsbury".

Tomlinson, 73, who found fame in the 1980s when he starred in long-running Channel 4 drama Brookside, said today he wants to clear his name before he dies.

"From day one I have believed this was a government set-up," he said.

"I'm 73, the oldest of the lads is in his mid-80s.

"We want the convictions quashed before we snuff it.

"What happened to us - and even worse what happened after Hillsborough - show the depths the establishment will sink too."

Campaign researcher Eileen Turnbull added: "The missing cabinet papers were not issued under the 30 year rule because the government cited 'national security' issues for them being withheld.

"Ricky and his team say the real reason is because they will expose involvement in the case at the highest government level, right to the door of Number 10."

The e-petition, which has been signed by around 1,150 people so far, requires 100,000 signatures to generate a Commons debate.

Earlier this year the campaign submitted a file on the case to the Criminal Cases Review Body requesting that the six convictions be quashed on the basis of "political interference".

Tomlinson will address the conference fringe meeting, at Manchester's Friends Meeting House, on Wednesday at 5.30pm.