The MP said he discussed the visa with the minister in the Commons

The Welsh Lib Dem leader mentioned Cheeky Girl star Gabriela Irimia's case to immigration minister Liam Byrne.

The Montgomeryshire MP, 41, recently announced the end of his engagement to ITV weather presenter Sian Lloyd.

Local party officials met him and said they accepted his explanation that there was no wrongdoing.

Officials had been concerned about the publicity surrounding the case and asked the MP to explain his actions.

It emerged on Wednesday that Mr Opik passed documentation onto the East Sussex constituency MP of Miss Irimia and her sister Monica, and spoke to Mr Byrne when they met in a corridor after the Cheeky Girls' application to remain in the UK was turned down.

Gabriela (R) says her friendship with the MP is "not a pantomime"

A Lib Dem spokesman said the MP had shown "total propriety" and had not lobbied on the singers' behalf.

But his local party demanded Mr Opik, their MP for nine years, explain himself.

On Thursday, Mr Opik told the BBC that he had asked Mr Byrne for advice on the issue and the minister had told him to pass it on to Miss Irimia's MP Michael Foster (Lab, Hastings and Rye) which he said he did by telephoning his office.

"I simply told Liam Byrne in the House of Commons what I had done and thanked him for his advice," said Mr Opik.

"I did not discuss the details of the case with him but simply told him I had taken his advice and passed the issue on to Gabriela's local MP."

Mr Opik hit the headlines last weekend when it emerged his two year engagement to Ms Lloyd, 48, was over and he was now going out with Miss Irimia.

The MP said he and Ms Lloyd had separated "some time ago" and it was "no secret" that he was seeing Miss Irimia.

The singer in turn has said their relationship was "genuine" and "not out of a pantomime".

He assured party officials there was no overlap in the relationships.

Mr Opik and Ms Lloyd recently separated

The Cheeky Girls arrived in the UK from Romania in 2002 and shot to fame with appearances on reality TV shows Popstars: The Rivals and Model Behaviour.

Their first single The Cheeky Song (Touch My Bum) climbed to number two in the charts.

The duo faced bankruptcy this summer when Telstar, their record company, collapsed.

Romania is due to join the European Union in January, which means its citizens will have the right to travel freely within Europe.

Self-employed people from the country are free to work in the UK after 1 January.

The Evening Standard reported that a Whitehall source said that the Cheeky Girls were not likely to be pursued for deportation.

When asked about the case by the BBC, Mr Byrne said he could not comment on individual cases.