British warships set sail for Gibraltar in show of strength as diplomatic row with Spain over border controls deepens

British warships are to visit Gibraltar in a show of strength in the stand-off with Spain over control of The Rock.

Three ships including the frigate HMS Westminster will sail for the region on Monday even as the diplomatic row with Madrid escalates over plans for draconian border controls.

The move comes just days after Gibraltar’s chief minister called for the British military to send forces into the area.

David Cameron yesterday warned his Spanish counterpart to back down in the row over controls at the border with Gibraltar.

The Prime Minister told Mariano Rajoy increased checks and plans to charge £43 to enter and leave the Rock were ‘totally disproportionate and unacceptable’ during a 15-minute phone call.

It was seen as coded warning that Britain is prepared to take Spain to court if it goes ahead with measures which are seen to be in breach of European law.

Officials admitted this could go as far as legal action in the European Court of Justice.

After the call, Mr Cameron vowed: ‘Britain will always stand up for the people of Gibraltar.’

But hopes he had won concessions from Mr Rajoy were dashed as officials continued to impose tough border controls.

News that British warships are heading to Gibraltar is likely to add to the tensions.

The Ministry of Defence stressed that the movement of the nine-vessel Response Force Task Group was ‘long-planned and well-established’.

Frigate HMS Westminster will lead the deployment to Gibraltar, along with Royal Fleet Auxiliary ships Lyme Bay and Mounts Bay.

A spokesman for the Ministry of Defence said: ‘Gibraltar is a strategic base for UK Defence and as such Royal Navy ships visit its waters throughout the year as part of a range of regular and routine deployments.