VOTERS across Britain are beginning to vote in this year's local government elections.

Polling stations opened at 7am for the ballot covering some 5,000 seats at stake on 181 local councils across England, Scotland and Wales.

Mayors will also be chosen in London, Liverpool and Salford, with 10 other major English cities holding referendums on whether to adopt the system of directly-elected civic leaders.

The complex electoral map is completed by ballots for the London Assembly.

Deputy Prime Minister Nick Clegg has voted in the Stannington area of Sheffield. The Lib Dem leader did not stop to answer questions as he went in and out of the Hall Park Centre, in his Sheffield Hallam constituency.

Voters will have to brave wet weather across much of Britain as they arrive at polling stations, which will stay open until 10pm.

Rain is often blamed for contributing to low election turnouts and forecasters have predicted downpours for Wales and central and southern England. But MeteoGroup, the weather division of the Press Association, said voters in northern England and Scotland should escape the wet weather, with dry and mild conditions expected.

Meteorologist Paul Mott said: "It will be a cold and wet morning for central and southern areas of England, and much of Wales. There'll be heavy rain across the south midlands throughout the morning, with patchy rain for parts of southern England, so it will be fairly wet for anyone venturing outside.

"The rain will ease later in the day but it will still be a cold and damp afternoon. In northern England and Scotland, though, it will be dry and very mild at about 18 or 19C, with the highest temperatures in Glasgow."

Nearly 15,000 candidates are battling for votes.