Simon Hughes has been named as the official Liberal Democrat candidate for the London mayoral elections.

The MP for Bermondsey and Southwark North fought off a tough challenge from the party's previous candidate Susan Kramer.

Hughes was confirmed on Wednesday after a ballot of party members.

On a turnout of 56 per cent he won 63 per cent of the votes - against Kramer who polled 34 per cent.

"I've done 20 years as a London MP. I've tried to help those in my bit of London," he said.

"London should be a place where everybody should be proud to live in, proud to work in and proud to visit all of the time," he told reporters.

He pledged to fight his campaign on making the capital a safer city, making the transport system reliable, reducing unemployment and supporting an Olympic bid.

Hughes repeated his support for the controversial congestion charge, claiming the Conservatives' opposition to the scheme would hit them hard.

"This is a huge chance for us. It's an election we believe we can win. We can overtake the Tories and we can beat the incumbent mayor," he said.

The Liberal Democrats are the last of the "big three" parties to confirm their candidate.

Hughes will go head to head with Labour's Nicky Gavron, Steve Norris for the Conservatives and current mayor Ken Livingstone.

Hughes claimed Livingstone would face a tougher contest this time as he was no longer "the folk hero returning from exile".

He refused to give any indication of who he would recommend voters backed as their second choice.

"We don't mind who you put second as long as you put Simon Hughes first," he said.

Currently the party's home affairs spokesman, Hughes is a former barrister who also stood in the 1999 leadership battle against Charles Kennedy.

Kennedy gave his support to "an exceptionally fine candidate" and said the campaign represented an "excellent opportunity" for the party.