It has been months since a senior Liberal Democrat fell victim to a sex scandal. So thank goodness for Lembit Öpik, the convivial MP who has swapped his weather girl fiancée for a member of the Cheeky Girls.

The party’s Wales and Northern Ireland spokesman woke yesterday to find his partner Sian Lloyd angrily calling off their engagement in one newspaper while his new Romanian friend extolled his love-making technique in another.

Until yesterday Mr Öpik, 41, a regular on TV chat shows, was best known for insisting that the Earth would be knocked sideways in a collision with an asteroid. Friends had expected him to marry Ms Lloyd, 48, one of ITV’s best known meteorologists. The couple had been together since 2000, but she has now spoken of her discovery that the MP’s attentions had wandered.

She said: “I found out from a mutual friend. I was in bed getting my beauty sleep when he was chatting up his Cheeky Girl. He’s the love of my life, but evidently he isn’t capable of an adult relationship.”

The new recipient of Mr Öpik’s affections is Gabriela Irimia, one half of the kitsch Romanian pop duo The Cheeky Girls, whose The Cheeky Song (Touch my Bum) was voted the worst pop record.

Ms Irimia, 23, said that her passion was inflamed after seeing Mr Öpik play the harmonica when they were both contestants on Five’s All Star Talent Show. She danced a ballet. They got together after meeting again at the Motor Neurone Disease Association annual ball late last month and became inseparable. “It was pure love, not ‘bang, bang’ sex and that’s it,” she told the News of the World.

Ms Lloyd blamed the House of Commons lifestyle for leading her man astray. “Lembit is a real barfly and there’s a massive drinking culture in the House of Commons,” she told The Mail on Sunday. “The drinking is beyond what most people would even begin to comprehend. It is hard core.”

Mr Öpik’s judgment has been questioned before. A keen supporter of Charles Kennedy until his party leader quit because of alcoholism, he then urged Mark Oaten to stand as Kennedy’s successor. Mr Oaten subsequently withdrew from the contest after revelations of a rent-boy scandal.

Mr Öpik released a statement yesterday confirming his Cheeky relationship and that he and Ms Lloyd had separated. He said: “It is true that the relationship between Sian Lloyd and myself ended some time ago. However, I continue to regard Sian as one of the brightest, most outgoing, hard- working and generous people I’ve had the privilege to know.”

The affair will add to the Liberal Democrats’ reputation for scandal-prone MPs. Simon Hughes, who was another of the party leadership candidates, was forced to admit that he had made misleading comments about his sexuality.

Times have also proved tough for The Cheeky Girls since the twins shot to prominence through the 2002 ITV Popstars talent search. Monica and Gabriela’s songs were written by their mother, Margit, who acts as their manager. But singles such as (Hooray, Hooray!) It’s a Cheeky Holiday and Cheeky Flamenco suffered diminishing chart returns. The girls faced bankruptcy this summer when Telstar, their record company, crashed.

Margit Irimia promised that the group would bounce back with a new cheeky girl, the twins’ six-year-old niece Lory, singing a new version of the Hokey Cokey. The trio released a download album in November titled In My Mind (Is A Different World — A Cheeky One).

She confirmed that Mr Öpik had already been to visit the family home in East Sussex. She said: “I saw it from day one. There is no doubt whatsoever that it is a genuine relationship.”

Ms Lloyd is keeping her engagement ring. “It’s Welsh gold and very special to me,” she said. “After all, I wouldn’t like to see it on the finger of a Cheeky Girl.”

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