A Spanish ship has illegally entered Gibraltar's territorial waters, the government has said.
"Illegal incursion into British Gibraltar Territorial Waters by Spanish Navy patrol ship Infanta Cristina this afternoon," the government of Gibraltar said on Twitter, alongside a video of the ship.
The news comes amid increasing tensions between the UK and Spain over the sovereignty of the rock.
Those tensions came to a head over the weekend when former minister Michael Howard suggested that Theresa May could go to war to protect the strategic enclave, a threat the prime minister did not immediately deny. Her spokesperson has since played down those comments.
The future Gibraltar is the first major dispute of the negotiations over Britain's exit from the EU, which began when Article 50 was triggered last week.
The Royal Navy told the ship to leave but the incident, the seventh of its kind this year, is likely to escalate already rising tensions over the sovereignty of the Rock.
Theresa May and Foreign Secretary Boris Johnson have moved to reassure the people of Gibraltar that the territory will remain under British control.
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