Argentina's President Cristina Kirchner and Britain's Prime Minister David Cameron clashed on Tuesday at the G20 summit over the future of the disputed Falkland Islands, officials said.

The pair came face to face at the meeting of the world's major economies in Mexico, at a time when tensions between their countries were already running high just after the 30th anniversary of the Falklands War.

Cameron urged Kirchner to respect the will of the 3,000 residents on the South Atlantic islands, who want to remain British. Kirchner countered him by citing UN resolutions calling for sovereignty negotiations.

"The president had the UN resolutions and she said to Cameron: 'Let's respect the United Nations'," Argentina's Foreign Minister Hector Timmerman said.

"The prime minister refused to accept the documents, turned his back and walked away without a farewell," he added, accusing Britain of disrespecting UN resolutions and of retaining a colonialist mindset.

A Downing Street source, speaking on condition of anonymity, confirmed that there had been an exchange, but downplayed the claim that Cameron had refused to accept a packet of documents from Kirchner.

Cameron had sought to urge Kirchner to respect the right of the Falklands' current residents to decide their own future in a referendum, the source said.

"He took it up to her to make those points. She took that badly and that was basically it," she said.

"I don't think it was actually totally clear that she was trying to give him documents.... We're following up with Argentinian officials here to see if there are any documents they want to give us."

In 1982 Argentina's former military regime invaded and occupied the Falkland Islands, which are known as the Malvinas in Spanish.

Britain promptly dispatched a naval task force to the South Atlantic and recaptured the territory after a brief but fierce war which left 255 British soldiers and 650 Argentines dead.

Argentina now has an elected civilian government and Kirchner has called for negotiations with Britain on the islands' future.

British officials accuse her of stirring nationalist passions for domestic political gain, and Cameron has refused to discuss the issue of sovereignty.