A Royal Navy patrol boat intercepted a Spanish vessel which had strayed into the waters of Gibraltar yesterday.
The Spanish Navy craft Infanta Cristina entered the British Overseas Territory’s waters on Sunday.
Pictures taken from the shore showed British vessel HMS Sabre – part of the Navy’s Gibraltar Squadron – challenging the Spanish incursion.
It is one of two Fast Patrol Boats – along with HMS Scimitar – with a top speed of 32 knots which keep watch over Gibraltar’s shores.
Little and large: The British patrol boat HMS Sabre (pictured front) intercepts the Spanish vessel Infanta Cristina (the larger one) off Gibraltar yesterday
The Gibraltar Squadron has 21 personnel and three Pacific ridge-hulled inflatable boats, according to the Navy’s website.
A UK Foreign Office spokesman said: ‘We can confirm an incursion by the Spanish navy occurred yesterday.
‘As with all incursions, the Royal Navy challenged the vessel. When challenged, the Spanish navy vessel left British Gibraltar territorial waters.
‘Incursions are a violation of sovereignty, not a threat to it. We have no doubt about UK sovereignty over Gibraltar, including British Gibraltar territorial waters.’
After a previous incursion in 2016 HMS Sabre fired flares at a Spanish research vessel when it strayed into Gibraltar’s waters.
The Royal Navy said at the time that it ‘challenges all unlawful maritime incursions into British Gibraltar territorial waters’.
‘We back this up by making formal diplomatic protests to the Spanish government,’ they said in November 2016.
The latest clash comes amid fears that a contract to build supply vessels for the Royal Navy could go to Spain.
The GMB said the £1 billion contract for Fleet Solid Support ships could go to the Navantia naval yard in northern Spain.
Incursion? The Spanish Navy craft Infanta Cristina is seen on Sunday when it is said to have entered the British Overseas Territory’s waters. A British ridge-hulled inflatable boat is seen nearer the front of the image
Union leaders said they had heard rumours that a decision to give the work to Spain could be linked to Brexit-related negotiations over the future of Gibraltar.
Gibraltar’s status flared up last year when Spain threatened to veto a Brexit deal if Madrid was not given guarantees over the Rock’s future.
Spain had demanded that the territory’s future be considered a bilateral issue between London and Madrid rather than between the EU and UK.
Britain’s ambassador to the EU promised in a letter that the Brexit deal did not restrict the ‘territorial scope’ of a future agreement.
Spanish PM Pedro Sanchez claimed victory and withdrew the threat of a veto.
Madrid’s foreign minister Josep Borrell went further, saying the agreement is ‘highly positive for Spain’.
Mrs May said it made no difference to Gibraltar’s constitutional status but was accused of ‘caving in’ to Spain’s demands.
Some 96 per cent of Gibraltar’s voters had backed Remain in the 2016 referendum.
Spain ceded control of the territory to Britain in a treaty signed in 1713 but has never relinquished its claim to Gibraltar.
Referendums held in 1967 and 2002 showed overwhelming support for continued British sovereignty in the territory.