Update | Britain warns of legal action as warships head for Gibraltar
British warships head to Mediterranean as Gibraltar dispute heats up

Britain warned Spain yesterday it might take legal action to try to force Madrid to abandon tighter controls at the border with the contested British overseas territory of Gibraltar in what it called an "unprecedented" step against a European ally.
The warning coincided with the departure of a British warship for Gibraltar, played down by the British and Spanish governments as part of a long planned, routine exercise but which underscored heightened tensions over the territory.
A spokesman for Prime Minister David Cameron said the Spanish border checks, imposed after Gibraltar created an artificial reef which Spain said blocked its fishing vessels, were "disproportionate" and "politically motivated".
Tensions over the rocky outpost at the mouth of the Mediterranean to which Spain lays claim have turned into one of the worst disputes in years between the two European Union members.
"The prime minister is disappointed by the failure of the Spanish to remove the additional border checks this weekend and we are now considering what legal action is open to us," Cameron's spokesman said, arguing they breached EU law.