The Conservatives and Liberal Democrats have set out their campaigns for the raft of elections on May 2.

On Monday the two parties joined the fight for the 9924 seats on England's local councils that are up for election next month.

With 22.4 million electors eligible to take part in the May 2 polls, the parties are facing the biggest test of their popularity in the country since last June's general election.

Labour is the biggest force in local government and will be fighting for 4895 seats, the Conservatives for 2732 and the Liberal Democrats for 1912. Independents account for 385 seats.

Of the 174 councils with elections, 75 are currently held by Labour, 32 by the Conservatives, 13 by the Lib Dems and 54 have no majority.

Labour, which launched its campaign last Thursday, has already warned that apathy among the electorate could see the far right BNP performing well in the northern towns hit by race riots last summer.

And party chairman Charles Clarke has sought to downplay possible losses, saying: "These are very tough elections. We are starting from a very high base."

Both the Opposition parties have focused on the claim that Labour is locally inefficient and is reducing democracy by centralising control.

The Lib Dems and the Conservatives will hope to make up ground on Labour, which has been hit by discontent among its grassroots supporters over the party's approach to public services as well as renewed allegations of sleaze and "cash for favours".

Conservative leader Iain Duncan Smith launched his party's campaign in Bradford today and his team will be hoping that an improved showing in recent opinion polls translates into significant gains.

Liberal Democrat leader Charles Kennedy is similarly looking for evidence that his party's claim to be the "effective opposition" is paying dividends.

The Liberal Democrats believe they can successfully defend the gains made from the Tories in the 1990s and take seats from Labour.

Lord Rennard, Liberal Democrat director of campaigns and elections, revealed at the party's campaign launch that focus will particularly be on Kirklees - where there is no overall control - Milton Keynes, Cheltenham, Eastbourne and Norwich.

The party will be defending control of the London boroughs of Islington, Sutton and Richmond, and the metropolitan boroughs of Liverpool, Oldham, Sheffield and Stockport.

"Low turn out is a worry," said Rennard. "The Conservatives do better on low turn out. We will show that we are a truly national party."

However, the Lib Dems have already had one set back.

In North London's Harrow Borough Council 60 of the party's candidates were barred from standing after they fell foul of new election rules.

On their nominations they described themselves as the "Liberal Democrat Focus team", after the title of their campaigning newspaper, leading the local returning officer to rule their election bids invalid under the Political Parties, Elections and Referendums Act which requires parties to register their names.