Oaten quits over rent boy scandal.
Mark Oaten last night resigned as Liberal Democrats home affairs spokesman after a scandal emerged over an affair with a rent boy.
The 41-year-old father of two apologised for the 'embarrassment' he had caused to his family and party.
In a statement last night, the man Welsh Lib Dem leader Lembit Opik had backed in the party's leadership race, said: 'I have stood down as home affairs spokesman for the party.
'I would like to apologise for errors of judgement in personal behaviour and for the embarrassment caused, firstly to my family but also to my friends, my constituents and my party.'
News of the World managing editor Stuart Kuttner said Mr Oaten's announcement came after he was confronted with details of the affair with the 23-year-old rent boy by the paper's reporters.
Mr Oaten's announcement is another massive blow for the party already reeling after Charles Kennedy was forced to quit just two weeks ago after admitting he had a drink problem.
Mr Oaten, who is MP for Winchester, last week pulled out of the race to succeed Mr Kennedy admitting that he lacked sufficient support among MPs to mount a credible leadership bid.
The statement continued: 'I will not be commenting further at this time and would now ask for some space and personal privacy for me and my family.'
Lib Dem chief whip Andrew Stunell confirmed that Mr Oaten had stood down 'with immediate effect' as home affairs spokesman.
'He has apologised to his family. He has apologised to his constituents who he always served well,' Mr Stunell said.
'He and his family now need to have their personal privacy respected.'
Mr Kuttner said that the News of the World had full details of what he said was a 'lengthy' affair with the rent boy - and which included three-in-a-bed sex.
Lembit Opik said he was unable to comment on the sudden resignation last night.