Libya has announced that it is halting oil deliveries to Switzerland and that it has withdrawn its money from Swiss banks.
According to the Libyan state news agency Jana, the sum concerned amounts to around SFr8 billion ($7.1 billion). It is the latest episode in diplomatic tensions between the two countries.
The Swiss foreign ministry said on Thursday evening that it had not yet received any official information from Libya on the situation.
Media reports quoted Issam Zanati, director of the Libyan Tamoil company, as saying the decision to halt the oil supplies had come from Libya, not the company.
He was unable to give any reason, or to say for how long deliveries would be suspended.
Farhat Qadara, head of Libya's central bank, told The Associated Press that "Libya has withdrawn all its deposits from Swiss banks and transferred them to other European banks".
The Jana report, said to be based on a Libyan foreign ministry official, confirmed the oil stop and said that it was in reaction to "abuse of Libyan diplomats and business people by the Geneva police".
These latest moves by Tripoli come three months after a diplomatic crisis erupted between the two countries, sparked by the arrest in Geneva of a son of Libyan leader Moammar Gaddafi, "Hannibal" and his wife. Servants of the two had accused them of serious mistreatment.
Libya took a number of measures against Switzerland at the time, including recalling some of its diplomats in Switzerland and detaining two Swiss nationals who were later released on bail but ordered to stay in Libya. It also threatened to halt oil supplies.
Although the charges against the couple were dropped after the servants withdrew their complaint, Libya has demanded that Switzerland apologise over the incident.
The Swiss foreign ministry still recommends that Swiss citizens do not travel to the country.
Analysts have speculated that the latest steps by Libya are an attempt to increase diplomatic pressure on Switzerland to close the case against Hannibal.
Rolf Hartl, managing director of the Swiss Oil Association, told the Swiss news agency that the country's oil supplies would not be affected. By the time any shortfall came to be felt, importers would have been able to compensate from other suppliers, he explained.
Switzerland imports about 20 per cent of its oil consumption from Libya. Libya owns one of the country's two oil refineries and 320 filling stations.
swissinfo with agencies
Libya is an important economic partner of Switzerland and its main supplier of crude oil.
Political contacts between the two countries also returned to normal after the UN-imposed sanctions were lifted in 2003.
Libya is one of Switzerland's five key export markets on the African continent.
In 1997 Tripoli banned Swiss citizens from entering Libya to protest against Switzerland's refusal to grant a student visa to a son of Colonel Gaddafi. In return the Swiss authorities tightened entry regulations for Libyan citizens. The conflict was solved in April 1998.
There are about 40 Swiss citizens in Libya, most of whom have dual nationality.