Speaking during a developing nation's meeting in Paris, Brazilian Foreign Minister Celso Amorim said Brazil was uncomfortable at the islands' inclusion in the proposed document, O Globo reported.
The Falkland Islands -- A British territory off the coast of Argentina -- have long been a point of contention between England and the South American nation.
In 1982, the two nations waged a short-lived war over the islands, leaving some 900 people dead, mostly Argentines.
Argentine officials are concerned that if the islands are included in the constitution as a British overseas protectorate, their ongoing struggle to regain control of them will be waged against the European Union and not just Great Britain.
2014: The Year in Music [PHOTOS]