The incendiary claim came from Conservative Michael Howard, who said Britain would do what it needed to keep the British territory. He alluded to Britain's protection of another rocky outpost 35 years ago as a precedent.
Gibraltar - the rocky British outpost on the southern tip of Spain - has been thrust into the Brexit spotlight after a former conservative leader in Britain said the country was prepared to go to war to defend it.
Michael Howard - a former head of Britain's conservative party, and a member of the Cabinets under Tory Prime Ministers Margaret Thatcher and John Major - provoked a firestorm Sunday with his incendiary comments during an interview with the British TV station Sky News.
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"I think there's no question whatever that our government will stand by Gibraltar," Howard said. "Thirty-five years ago this week another woman prime minister sent a task force half way across the world to defend the freedom of another small group of British people against another Spanish speaking country, and I'm absolutely certain that our current prime minister will show the same resolve in standing by the people of Gibraltar."
Howard was referring to the 74-day war between the United Kingdom and Argentina in 1982 after the latter's Junta regime seized the Falkland Islands off the Argentine coast - 35 years to the day (April 2).
Three days later then British Prime Minister Margaret Thatcher dispatched a naval force to take back the territory. Argentina surrendered on June 14.
A veto for Madrid
Britain's Defense Secretary Michael Fallon echoed Howard's comments, but in a less provocative manner. Fallon said during an interview on the BBC's Andrew Marr show that Gibraltar would be protected "all the way."
The issue broke into the public sphere a day after the European Union proposed offering Spain a right to veto over Gibraltar's future trade relations with the bloc.
The veto would give Madrid sway over the fate of the enclave once Britain has left the bloc, meaning the status of its overseas territory is no longer an internal EU matter.
Spain ceded the rocky outpost - just eight miles across the mouth of the Mediterranean Sea from Morocco - a little more than 300 years ago, but has long sought to have it returned. The power of a veto over trade relations between Gibraltar and the EU would put Spain in a powerful position concerning the strategically important outpost.
In 2002 voters in Gibraltar rejected the idea of Britain sharing sovereignty with Spain by 99 percent to 1 percent. But the predominantly British population overwhelmingly backed remaining in the EU in last June's Brexit referendum.
Spain's foreign minister Alfonso Dastis refused to talk about veto rights when it comes to Gibraltar in an interview on Sunday, but said he viewed the EU's stance very positively.