Britain has appealed to Interpol to reject Argentina’s requests for the arrest of individuals involved in a large oil project off the Falkland Islands.

With tensions over the sovereignty of the British overseas territory reaching levels not seen since the war with Argentina in 1982, UK officials have sought urgent assurances from the international organisation.

A letter has been sent to Interpol’s headquarters in Lyon arguing that “red notice” requests from Argentina for the arrest of such individuals, including British nationals, should be seen as politically motivated.

It is understood the UK government is concerned by what sources suggested was an attempt to bully people and companies out of working in the Falklands.

An oil project known as Sea Lion in the North Falkland Basin in the south Atlantic has the potential to triple the Falklands’ GDP but Argentina’s president, Javier Milei, has vowed to block it. Argentina’s strategy includes attempts to criminalise those involved in Sea Lion and deter other investors.

In its letter, the UK government has urged Interpol to be cautious in its handling of Argentinian requests for detentions, it is understood.

Andrea Clausen, the chief executive of the Falklands government, confirmed that the use of Interpol by Argentina was a threat but added: “One would hope that Interpol wouldn’t necessarily take action.”She said: “Certainly those of us who have an interest have had a look at certain sections of Interpol’s constitution to see what we think it could mean.”It is understood that a response from Interpol to the UK government’s correspondence stated that it would respect article 3 of its constitution, which forbids it from undertaking any intervention or activities of a political character.

Interpol screens red notices, which are requests to locate and provisionally arrest a person pending extradition. If circulated to the enforcement agencies, individual member countries then decide whether to act on the requests. Nearly 20,000 were issued last year.

The foreign secretary, Ed Miliband, has told MPs that the UK will protect businesses working in the Falklands from pressure from Argentina through measures under protection of trading interests (PTI) legislation.

The legislation allows the UK to issue orders and directions forbidding British individuals and companies from complying with specific foreign laws or trade controls. It also opens up the possibility that those affected by Argentinian legal pressure could claim damages in UK courts.

Miliband said: “The UK’s support for the Falkland Islands is steadfast. Argentina’s attempts to intimidate businesses and individuals engaged in legitimate commercial activity are unacceptable. Companies should be free to make lawful commercial decisions without the threat of political coercion.

“We will always stand up for the Falkland Islanders, their right to determine their own future, and their right to pursue legitimate economic development.”The intensity of Argentinian pressure relating to the Falklands is at a level that UK officials say has not been seen since the war 44 years ago that followed the invasion ordered by the then Argentinian dictator, Gen Leopoldo Galtieri.

The 74-day conflict ended with the surrender of the Argentinian forces and cost the lives of 649 of its military personnel, 255 British military personnel and three Falkland Islanders.

Argentina continues to claim sovereignty over the 700 islands that make up the Falklands and has dismissed a 2013 referendum in which 99.8% of the islands’ 3,600 residents voted to remain a British territory, with only three votes against.

Despite Interpol’s reassurance about its screening of red notice requests, concerns remain that Argentina could convince the organisation’s member states that its requests are not political but rooted in domestic legislation.

Milei has initiated criminal proceedings against the Israeli company Navitas and its British partner, Rockhopper Exploration, which are the core companies in the offshore Sea Lion project.

A draft national sovereignty bill introduced to Argentina’s congress would further expand the scope of sanctions to affiliates of those companies, financial intermediaries, shareholders and suppliers.

The bill additionally contains clauses that could target those involved in the fishing industry in the Falklands, which makes up a large part of the islands’ economy. The archipelago is 300 miles (500km) east of the southern Patagonian coast of Argentina.

Workers in the oil and fisheries sectors on the Falklands – known in Argentina as Las Malvinas – are understood to be concerned that they could be targeted should they travel, particularly to South America, where there is support for Buenos Aires’s sovereignty claim.

In a tandem move to kill off Sea Lion, Argentina is expected within 24 hours to escalate further its dispute with the UK by requesting arbitration under annex VII of the UN convention on the law of the sea (Unclos) over the oil project.

On 28 September, Milei gave the UK a two-week deadline to stop the project or face such legal action. The deadline passed on Monday and Argentinian newspapers said an application for arbitration would follow.

Under it, Buenos Aires will claim the UK is in breach of a UN resolution inviting the parties to negotiate over the sovereignty dispute and refrain from “unilateral modifications” to the situation. It will be seeking a binding ruling that the UK must stop the drilling. However, UK government sources are confident that Unclos will not wade into a sovereignty dispute.

At a public meeting on Monday evening, one of the Falkland Islands’ assembly members, Dean Dent, told constituents that the UK government was working hard on a tough response to the Argentinian Unclos threat.

“The UK government has assembled quite an in-depth team of legal advisers, KCs – that is the first step,” he said. “There have been four recent similar cases where a case of sovereignty has been taken to Unclos and all four were disregarded by the tribunal as all four cases were a sovereignty issue, not a maritime issue.”The UK government is expected to be increasingly muscular in its approach to Argentina in the coming days. The prime minister, Andy Burnham, told parliament on Monday that he had raised the issue and “the clear and declared will of the islanders to remain British” with the US president, Donald Trump.