Shouldn't Spain give Olivença back to Portugal?
Olivenza (Spanish) or Olivença (Portuguese) is a town in the autonomous community of Extremadura, situated on a disputed section of the border between Portugal and Spain. Olivenza is claimed by both countries and is currently administrated by Spain.
Olivenza had been under undisputed Portuguese sovereignty since 1297 until it was occupied by the Spanish in 1801, and formally ceded by Portugal, after being invaded and defeated by Spain at the War of the Oranges, later that year by the Treaty of Badajoz.
Spain claims the "de jure" sovereignty over Olivenza on the grounds that the Treaty of Badajoz still stands and has never been revoked. Thus, the border between the two countries in the region of Olivenza should be as demarcated by that treaty. Though, the terms of the very Treaty of Badajoz undoubtedly state that if war was ever to again occur between the two countries, then the Treaty would be void. And that happened when Spain itself later invaded Portugal.