The action could close schools, libraries and sports centres. Traffic problems are expected in some cities, and refuse collection will also be hit.

The 11 trade unions involved are angry at government plans to scrap a rule that allows some to retire on a full pension at 60.

But the government says the current rule is discriminatory and must go.

The unions say it could be the biggest stoppage in the UK since the General Strike in 1926.

Workers expected to walk out include leisure centre workers, school staff including caretakers, cooks, cleaners and office workers, refuse collectors, housing officers, nursery nurses, youth and community staff and tourism officials.

Unions taking part include Unison, T&G, GMB and Amicus.

Major disruption caused by the strike is set to include:

* The closure of thousands of schools across the UK

* Traffic chaos on Merseyside with the Mersey tunnels and the Mersey ferry to close forcing motorists to take a 40-mile detour via Runcorn Bridge

* The Tyne Tunnel and the Metro in danger of closure in Newcastle

* Picket lines across Scotland and rallies in Glasgow and Edinburgh

Unison's Heather Wakefield said unions had been "pushed into this in order to demonstrate to the government and the local government association just how essential our members are".

"Unfortunately we think that most schools will be closed" - Heather Wakefield, Unison

She said a wide range of services could be hit.

"Unfortunately we think that most schools will be closed, that public transport will be hit and in some places police and fire control rooms will be hit.

"Refuse collection will be hit as will the whole range of public services that our members provide."

On the issue of school closures, Education Secretary Ruth Kelly said in the Commons on Monday that staff should think carefully before striking.

"I would urge any staff that are involved to think seriously about the consequences for schools, particularly those who serve special needs children," she added.

Rule 85

Unions have warned of further action in the run-up to the local council elections in May.

"Local authority employees in unions are saying 'we're special, we're more special than you, we want to retire at 60' " - Digby Jones, CBI

At the centre of the dispute is the so-called Rule 85 - which lets staff retire at 60 if their age, plus years worked, equals 85 or more.

If the rule ends, all two million local government workers will work until the age of 65 by 2013.

The unions want workers who signed up for the scheme to have their pension rights protected.

They say this would be treating them in the same way as uniformed police, NHS workers, civil servants and teachers - who can all retire on full pension at 60.

But Sir Digby Jones, director general of the CBI, told BBC News he thought the strike was "a disgrace".

Pensioners and "the lower paid" would suffer most because they "rely on local authorities so much more", he said.

"And why? Because local authority employees in unions are saying 'we're special, we're more special than you, we want to retire at 60'.

"And everybody in the private sector - 14 million people in this country - are being told they've got to work until 65, 67, 68."

Union talks

The Office of the Deputy Prime Minister says the rule - which is scheduled to be scrapped in April - must be replaced for all workers.

It says women tend to join the workforce later and take career breaks which makes the current regime discriminatory.

The department held a three-month consultation on the issue, which finished on 28 February.

Talks between Deputy PM John Prescott, the unions and the Local Government Association - which represents local authorities in England and Wales - continued until 14 March when eight trade unions voted for strike action.