Tory MEPs are demanding authorities rein in a Spanish politician after he told Argentinean officials the European parliament did not recognise British sovereignty over the Falklands.
Socialist MEP Luis Yañez Barnuevo was leading a parliamentary delegation to Buenos Aires on trade talks concerning the South American Mercosur block when the subject of the Falklands was raised by the Argentineans.
"British sovereignty over the Malvinas Islands as such is not accepted by the European parliament," Barnuevo is reported to have said.
The parliament has not passed any resolution opposing or questioning UK sovereignty over the Falklands.
Charles Tannock MEP, Conservative spokesman on foreign affairs, is to ask president of the parliament, Martin Shulz, to look into Barnuevo's conduct.
Separately, MEP Martin Callanan, leader of the European Conservatives and Reformists Group, also plans to raise the issue at the next Conference of Presidents, the regular business meeting of the parliament's political leaders.
"Barnuevo had no power, authority or any kind of mandate to say what he did," Tannock said.
"If he had been giving a personal view that might have been a little better, though still unacceptable; but to claim that he was speaking for the parliament was entirely inappropriate.
"The European parliament has no role in recognising sovereignty. It is entirely a matter for the member states and will remain so.
"He should be required to explain himself and be reminded where his responsibilities begin and end."
A recent referendum on the Islands saw overwhelming support for the territory to remain British, but Argentinean president Cristina Fernandez de Kirchner continues to regularly return to the subject, which serves to unify voters in Argentina.