THERESA May has said Gibraltar will remain British for "as long as it chooses to do so" and will be "fully involved" in Brexit talks.
The British prime minister sought to give assurances to the British overseas territory in a message broadcast to mark Gibraltar National Day.
Spain has a long-standing territorial claim on Gibraltar, which has been held by the UK since 1713 and has the status of a British overseas territory.
But Spain's foreign minister Alfonso Dastis last month said his country will not push its sovereignty claim over the Rock by making it a condition of any UK-EU Brexit agreement.
Mrs May said: "As the UK negotiates to leave the European Union, Gibraltar will be fully involved.
"As we face the opportunities and challenges to come, the UK will continue to stand firmly beside you. We will resolutely safeguard Gibraltar, its people and its economy.
"And Gibraltar will remain British for as long as it chooses to do so."