Image caption Falkland Islanders voted earlier this year to stay a British territory

Argentina has threatened oil businesses operating off the Falkland Islands with fines, confiscations and jail sentences for their executives.

Argentina's embassy in London said new laws had been passed by the country's congress to clamp down on exploration it claims is in breach of UN decisions.

The UK's Foreign Office insisted the activities were legitimately controlled by the islands' government.

Islanders recently voted overwhelmingly to remain a British overseas territory.

The embassy said legislation "provides for prison sentences for the duration of up to 15 years; fines equivalent to the value of 1.5 million barrels of oil; the banning of individuals and companies from operating in Argentina; and the confiscation of equipment and any hydrocarbons that would have been illegally extracted".

Stepped up claims

It said in a statement: "The Argentine government has protested against and rejected all of the United Kingdom's attempts to promote and authorize such hydrocarbon exploration and exploitation activities in the area of the Argentine continental shelf.

"These attempts are manifestly contrary to Resolution 31/49 of the United Nations General Assembly, which requires the UK and Argentina to refrain from taking decisions that would imply introducing unilateral modifications into the situation of the Malvinas Islands while the sovereignty dispute between the two countries is still pending."

In a referendum in March, Falkland Islanders decided by 1,513 votes to three to remain a UK overseas territory but Argentina - which calls the islands the Malvinas - has stepped up its claims to them at the United Nations.

A Foreign Office spokesman said: "Hydrocarbons activities by any company operating on the continental shelf of the Falkland Islands are regulated by legislation of the Falkland Islands government, in strict accordance with the United Nations Convention of the Law of the Sea.

"As such these activities are wholly legitimate and legal. The UK government unequivocally supports the right of the Falkland Islanders to develop their natural resources for their own economic benefit.

"This right is an integral part of their right of self-determination, which is expressly contained in the International Covenant on Civil and Political Rights.

"Argentine domestic law does not apply to the Falkland Islands or South Georgia and the South Sandwich Islands, which are UK overseas territories."

Image caption The Falkland Islands and South Georgia and South Sandwich Islands are British Overseas Territories

Argentine forces invaded the Falkland Islands on 2 April 1982 and surrendered after two months of fighting.

A total 255 British and about 650 Argentine servicemen were killed, along with three Falkland civilians.