Argentina is protesting Britain's decision to name a vast swath of Antarctica as Queen Elizabeth Land.
The foreign ministry has handed a formal protest note to British Ambassador in Buenos Aires.
The note rejects London's claim since 1908 to a chunk of Antarctic known as the British Antarctic Territory, and it criticizes what Argentina calls Britain's "imperialistic ambitions going back to ancient practices."
Argentina has long claimed as its own the land named after the British monarch this week. That area is about a third of the British Antarctic Territory.
Argentina also claims the British territory of the Falkland Islands, which are known as Las Malvinas in Spanish. The two nations fought a brief but bloody war over the South Atlanticarchipelago 30 years ago.