Geneva - ABB, the power technologies group, said Friday it was concerned for the fate of its employee in Libya who has not had any contact with the firm in five weeks, a day after the Swiss government express increased frustration with Tripoli.

"ABB is deeply concerned at the disappearance of the company's Libya country manager Max Goldi. ABB is very disturbed that it has not heard from Mr Goldi or received any sign of life for five weeks," Joe Hogan, the chief executive officer, said in a statement posted on the company's Website.

His rare public comment came a day after Switzerland's government said it was disappointed with "the systematic refusal" of Tripoli to cooperate on an agreement signed two months ago to restore diplomatic relations between the countries and return two detained Swiss nationals.

The two, taken 15 months ago, were initially in contact with the embassy and their families, but have now not been heard from since September 18. The government in Bern has said their whereabouts are unknown.

"ABB urges the Libyan and Swiss governments to continue their efforts to bring this deeply worrying situation to a successful humanitarian conclusion as a matter of urgency. ABB appeals to the international community to support this effort actively," said Hogan, adding that he was "grateful" for Bern's efforts to date.

"The problem is not with Switzerland, the problem is with Libya," said Micheline Calmy-Rey, the Swiss foreign minister a day earlier, terming the two as "kidnapped."

The row started last summer, when the Geneva police arrested Hannibal Gaddafi and his wife. The couple were accused of beating their servants at a high class hotel.

Gaddafi, the son of the Libyan leader Muammar Gaddafi, was released back to Tripoli two days later. But trade between the two countries dwindled to a trickle, flights were canceled and generally bad relations ensued. And the two Swiss nationals were arrested.

In August, Swiss Finance Minister Hans Rudolph Merz, who also holds the rotating presidency, traveled to Libya and signed an agreement to restart diplomatic ties. But, although the two-month deadline passed this week, no tangible progress has been made.

Calmy-Rey and Merz gave no further details but implied Bern might alter its strategy, as popular upset and frustration among the Swiss population continued to grow. (dpa)