Argentine President Javier Milei accused the United Nations of failing to enforce its own resolutions Wednesday and warned Argentina would act independently as tensions rise over British-backed oil development near the Falkland Islands.

Milei used his address to the U.N. General Assembly in New York to renew Argentina’s longstanding claim to the Falkland Islands, known in Argentina as the Malvinas, while directing much of his criticism at the international organization for failing to resolve the sovereignty dispute with Britain.

“Argentina is not going to sit and wait for the U.N. and the international community to live up to their own mandate,” Milei said. “It will take matters into its own hands.”

The warning comes as a major offshore oil project raises the stakes surrounding the disputed territory. The Sea Lion project, located roughly 140 miles north of the islands, is being developed by Britain’s Rockhopper Exploration and Israel’s Navitas Petroleum. The companies are planning to begin drilling in the coming months, with oil production expected in 2028. Argentina considers the project an unlawful exploitation of resources in waters it claims.

Milei pointed to U.N. General Assembly Resolution 31/49, adopted in 1976, which calls on Argentina and the United Kingdom to refrain from unilateral actions that could complicate the sovereignty dispute while encouraging negotiations. He argued that decades of resolutions have produced little progress while Britain continues to develop resources around the islands.

Argentina has already taken legal and economic steps against the oil project. Milei's government has initiated sanctions proceedings against companies and individuals connected to offshore drilling, while his administration has submitted legislation to Congress seeking tougher penalties for companies involved in resource development around the Falklands. An Argentine federal judge also recently ordered British and Israeli companies to halt development of the Sea Lion project pending an environmental review.

Britain maintains control of the Falkland Islands and rejects Argentina’s sovereignty claim. British officials have also defended the islanders’ right to determine their own political future. In a 2013 referendum, 99.8% of voters chose to retain the territory’s status as a British Overseas Territory.

Milei rejected that argument in his U.N. address, saying the principle of self-determination does not apply because, in Argentina’s view, the current population was established by the occupying power on territory whose sovereignty remains disputed. Britain maintains the opposite position and says its commitment to the Falkland Islanders’ right to self-determination is firm.

Argentina and Britain fought a 74-day war over the islands in 1982 after Argentine forces invaded the territory. British forces ultimately retook the islands, and the dispute has remained unresolved for more than four decades. The United Nations continues to treat the sovereignty question as a dispute between the two countries and has called for a peaceful resolution through negotiations.

Milei’s latest remarks mark another escalation in Argentina’s campaign over the Falklands as offshore oil development gives the decades-old sovereignty dispute a new economic dimension.