At the Rio Group summit of 32 countries hosted by Mexico, Argentina presented a statement quoting Mexican President Felipe Calderon as saying that "the heads of state represented here reaffirm their support for the legitimate rights of the republic of Argentina in the sovereignty dispute with Great Britain."
Calderon did not speak directly about the matter.
Britain and Argentina have long disputed sovereignty of the Falkland Islands — known as Las Malvinas in Latin America — and fought a war over them in 1982.
The issue had been relatively calm until a British oil exploration company recently announced drilling plans there.
Desire Petroleum PLC said Monday that it has started drilling for oil about 60 miles (100 kilometers) north of the disputed Falkland Islands, despite strong opposition from Argentina. The country claims the south Atlantic islands as its own and calls them Las Malvinas.
"The well is being drilled to an estimated target depth of circa 3,500 meters (11,500 feet)," the company said in a statement. "Drilling operations are expected to take approximately 30 days."
The dispute over the Falklands dates back to the 19th century, when the islands were seized by the British. Argentina has sought their return ever since, invading in April 1982 and holding them until June, when British forces retook the territory.
Full diplomatic relations were restored in 1990 and both sides have since largely agreed to disagree on the issue of sovereignty. But anger over the issue still lingers and has been exacerbated by the prospect that Argentina could lose out on mineral wealth discovered offshore.
Argentine President Cristina Fernandez ruled out any plans to try to keep the British boats or rigs out. "We do not believe in methods like blockades," she told reporters.
One of the primary goals of the two-day summit being held in the Caribbean beach resort of Playa del Carmen is the formation of a new regional group that would include all nations in the Americas — except the United States and Canada.
A working summit document, a copy of which was obtained by The Associated Press, suggests diplomats are still working on a name for the organization, with the "Latin American and Caribbean Community" being one possibility. The group is expected to be established by 2011.
The summit meeting was marked by a strong exchange of words between leftist Venezuelan President Hugo Chavez and Colombia's conservative Alvaro Uribe, said a diplomat with firsthand knowledge of the situation.
The discussion centered on political differences that have led Venezuela to suspend many of Colombia's exports, and reached such a heated level that Chavez reportedly got up to leave the meeting before other leaders stepped in to calm the two, said the diplomat, who was not authorized to be quoted by name or country.
