Their dispute over Gibraltar has flared again.
Britain has accused Spain of violating its sovereignty by repeatedly and unlawfully entering the rocky outcrop’s territorial waters.
“These repeated incursions into British Gibraltar territorial waters are a clear violation of UK sovereignty by another EU country and we will be raising this as a matter of urgency with the Spanish authorities,” Hugo Swire, a British Foreign Office minister, said in a statement on Sunday.
Swire said he deemed it “completely unacceptable and unlawful” under the international law of the sea for Spain to enter Gibraltar’s territorial waters without notification.
But Spain denied wrongdoing.
“The waters are Spanish,” said an official from Spain’s Foreign Ministry, who declined to be named in line with the ministry’s policy.
“It was Spanish boats patrolling in Spanish waters to control illegal activities such as tobacco smuggling or illegal fishing.”
The row is the latest in a long line of diplomatic spats between Britain and Spain over Gibraltar, which was ceded to Britain about 300 years ago but which Spanish authorities now want to reclaim.