Police visit Sarkozy HQ in L'Oréal probe

The visit on Wednesday marked the first time Mr Sarkozy's ruling UMP party has been directly targeted by the investigation that started in June.

A police spokesman said officers were seeking to trace a letter sent in 2007 by Labour minister Eric Woerth, then UMP party treasurer, to then-interior minister, Mr Sarkozy, backing the granting of a national award to a man who was wealth manager for the L'Oral heiress Liliane Bettencourt and who employed Mr Woerth's wife.

The party confirmed the police visit but said this did not amount to a raid. "The police came to our office to seek information. We agreed to open our doors," a UMP spokeswoman said, declining to elaborate on the police requests.

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What began as a family feud between Mrs Bettencourt, 87, and her daughter has exploded into a series of investigations concerning political donations, suspected tax evasion and alleged money laundering.

Mr Woerth, a close ally of Mr Sarkozy, who is also in charge of pushing a controversial pension reform bill through parliament, has acknowledged that he intervened on Patrice de Maistre's behalf concerning the prestigious lgion d'honneur award.

He has come under pressure to resign after it emerged his wife worked for the Bettencourt wealth manager amid broader allegations that he handled funds used for Mr Sarkozy's successful 2007 election campaign.

Mr Woerth and Mr Maistre have repeatedly denied the allegations and Mr Woerth insists his involvement in the lgion d'honneur was nothing more than routine business for a member of parliament. Mr Maistre received the lgion d'honneur in early 2008, two months after Mr Woerth's wife was recruited to work at the firm, Clymene, which manages Bettencourt's vast fortune.

Mr Sarkozy attempted to defuse the growing scandal, which has helped drive his approval ratings to a record low, by making a rare summer address to the nation the day before his pension reform package was presented to the cabinet.

Despite isolated calls for Mr Woerth to resign, or for Mr Sarkozy to bring forward a cabinet reshuffle planned for October, the president seems determined to tough it out in the hope that the story will die away during the holidays.

Critics have claimed his government is in crisis.

"There's nothing more (Mr Sarkozy] can do by talking, the French are waiting for action," Jerome Cahuzac, the socialist president of the finance commission, said.

"The events are all as sordid as each other. The French can no longer accept this decay," centrist leader Franois Bayrou told Europe 1 radio.Mr Woerth has previously said that he wanted to be given a hearing as quickly as possible in order to prove his innocence.

An inquiry into the affair "is a good thing, it allows you to tell the truth", he said.