The men were held at an undisclosed location before arriving at the embassy

Two Swiss businessmen detained in Libya for more than a year are to be put on trial for tax evasion and visa irregularities, Libyan officials say.

Max Goeldi and Rachid Hamdani were refused exit visas in July 2008, soon after the arrest in Geneva of a son of Libyan leader Muammar Gaddafi.

They were handed over to the Swiss embassy in Tripoli on Monday, fuelling expectations they would be released.

But foreign ministry official Khaled Keim said they would stand trial.

Mr Keim called on Switzerland not to make any links between the case and the issue of what he called the "aggression" against Col Gaddafi's son, Hannibal.

"They will be tried and charged with non respect for residence visa procedures and tax evasion," he said in a statement on Thursday, quoted by Reuters.

Charges dropped

Hannibal Gaddafi and his wife were arrested at their luxury hotel in Geneva in July 2008 after being accused of mistreating two of their servants.

The charges were later dropped, but the case angered Tripoli.

Their arrest sparked retaliatory measures from Libya, including cancelling oil supplies, withdrawing billions of dollars from Swiss banks, refusing visas to Swiss citizens and recalling some of its diplomats.

Mr Goeldi and Mr Hamdani were stopped from leaving the country days after the arrest.

Swiss President Hans-Rudolf Merz apologised for the arrests in August - in a move many hoped would secure the businessmen's release.0

But the pair were held at an undisclosed location until being handed over to the Swiss embassy.

Mr Keim said they must now leave the embassy and choose another place to stay so they can be reached by their lawyers and law enforcement officials, Reuters reported.