Spain currently holds the rotating six-month presidency of the EU and was widely expected in Argentine diplomatic quarters to be more sympathetic than other European states to Argentina's current campaign to bring its claims over Falklands to an international forum.
Argentina renewed its claims over the Falkland Islands, which it calls Malvinas, in a response to the start of British oil prospecting in the South Atlantic waters, believed to hold the largest reserves of oil and gas outside Saudi Arabia.
Argentina invaded the islands in 1982, when it was under military dictatorship but was beaten back by a British task force. The war lasted 74 days and resulted in the deaths of 255 British and 649 Argentine troops and three civilians.
The Falkland Islands, about 400 miles off Argentina's southern coast, have been governed from London since 1833 but Argentina maintains they are part of its territory.
The European Union's response made clear the European governments considered the dispute a bilateral issue between Argentina and Britain and ruled out any EU role in resolving differences between London and Buenos Aires.
A Spanish government statement went further, emphasizing that the issue was not even regional and needed resolution between the two countries, a marked departure from the position adopted at a recent summit of Central and South American countries at Cancun, Mexico. At the meeting Argentina won support from its neighbors that prompted Buenos Aires to approach the U.N. and the U.S. administration.
The U.S. administration has already made clear it wants Argentina to talk things over with Britain rather than seek a U.S. mediation role. U.S. Secretary of State Hillary Clinton met with Argentine President Cristina Fernandez de Kirchner during her Latin tour this week and ruled out any U.S. involvement.
Analysts said the EU response meant Fernandez would be hard put to sustain her current effort to internationalize Argentina's claims over the Falklands, despite the support she received at the Cancun summit.
Argentina's Falklands campaign coincides with escalating economic and political problems for Fernandez.
The Washington Post commented, "You know that an Argentine leader must be in political trouble if the subject of the Falkland Islands has come up again." It said Fernandez "has lost the support of most of the country."
The paper said, "It's hard to see why the Obama administration should throw any lifelines to Fernandez de Kirchner, who hasn't shrunk from playing to anti-American sentiment around the region."