Dozens of demonstrators burned Union Jack flags and an effigy of Prince William in front of the British Embassy in Buenos Aires Monday, which marked the 30th anniversary of Argentina's invasion of the Falkland Islands.
While President Cristina Fernández de Kirchner was holding an observance ceremony in Ushuaia province in the south with Falkland War veterans and government officials, members of radical groups in the capital battled with riot police as they tried to break through barriers protecting the diplomatic mission.
London condemned the violence and asked the Fernández de Kirchner government to comply with its international obligations to protect diplomatic missions.
No one was injured in the confrontation, which began in the afternoon when protestors from the Workers Party, the leftwing Quebracho organization and other groups started hurling rocks and Molotov cocktails inside the embassy's compound. Riot police fired tear gas and rubber bullets in an effort to repel the demonstrators.
Some protestors, who identified themselves as Falkland War veterans, delivered speeches demanding that British companies be ejected from Argentina.
Tensions between London and Buenos Aires are at their highest level since Britain and Argentina fought a 10-week war over the South Atlantic islands in 1982 in which 649 Argentineans and 255 Britons died.
In Ushuaia, the province Argentina says will administer the Falklands once they change hands, Fernández de Kirchner again called on the British government to begin dialogue to start transfer of the islands.
In London, British Prime Minister David Cameron again said that the Falklands are not negotiable because islanders have decided they want to remain British.