BRUSSELS: The European Commission said Tuesday it had begun looking into a Spanish complaint over the creation of a concrete reef off Gibraltar, a move that triggered a bitter diplomatic spat between London and Madrid.
"As soon as we receive a formal complaint from a member state, we are obliged to launch a complaint procedure, which could in turn lead to an infringement procedure," spokesman Olivier Bailly said.
He said such a procedure into a breach of EU law would only be launched if "we were able to confirm the facts and were not convinced by the answers Gibraltar and the United Kingdom provide".
"Obviously, we're not there yet," Bailly added.
The Spanish complaint argues that the 70 concrete blocks dropped into the waters of Gibraltar, a self-governing British territory, contravene EU directives on protecting the environment.
The Gibraltar government says the reef will regenerate marine life and argues that the Spanish raked for shellfish there illegally in its waters.
Spain says its sovereignty over the waters is not in doubt, arguing that they were never included in the 1713 Treaty of Utrecht under which Spain ceded Gibraltar to Britain in perpetuity.
Spain stepped up checks at the border with Gibraltar this month saying it was cracking down on smuggling but creating hours-long traffic queues.
Britain accuses Madrid of using the border to retaliate over the reef.