Gibraltar: The 'Party Is Over' Warns Spain

Britain says it is concerned by comments made by Spain's foreign minister in which he warned the "party is over" when it comes to his country's policy on Gibraltar.

Jose Manuel Garcia-Margallo said he was considering retaliatory measures towards the British territory, including a 50 euro border crossing fee, amid a dispute over an artificial reef being created by the Gibraltarians.

He told ABC newspaper the proceeds would be used to help Spanish fisherman who have lost out because of damage to fishing grounds allegedly caused by Gibraltarian authorities.

Mr Garcia-Margallo added that tax investigations into thousands of Gibraltarians who own property in Spain could also be launched.

Spain is also considering closing airspace to planes heading to Gibraltar airport, he added, as well as changing rules to increase tax revenue from online gaming companies based on "the Rock".

A Foreign Office spokesperson said: "We are concerned by today's comments on Gibraltar, which we are looking into further.

"As we have said, we will not compromise on our sovereignty over Gibraltar, nor our commitment to its people. We continue to use all necessary measures to safeguard British sovereignty."

The comments come after "disproportionate checks" at the border have increased tensions between Britain and Spain.

The Spanish ambassador was summoned to the Foreign Office last week to explain why people crossing the border were having to wait up to seven hours in sweltering heat.

Foreign Office Minister Hugo Swire said the delays were "as a result of wholly disproportionate checks introduced by the Spanish authorities on vehicles both leaving and entering Gibraltar".

Foreign Secretary William Hague also called Mr Garcia-Margallo to express concern over the delays.

Britain has held sovereignty over Gibraltar for three centuries and its 2.6 square miles is home to 30,000 people, with an economy dominated by off-shore banking, internet gambling operations and tourism.

However, ownership of the territory has long been a point of contention between Spain and Britain.

The latest tensions began 10 days ago after Gibraltarian boats began dumping blocks of concrete into the sea near the territory.

The British territory said it was creating an artificial reef that would foster fish populations, but Spain said the reef would block its fishing boats and ramped up border checks.

Gibraltar has complained to the European Commission, saying the checks violate EU rules on free circulation.

Spain's previous government took a softer line on Gibraltar and did not discuss the issue of sovereignty, but Spanish Prime Minister Mariano Rajoy, who was elected in November 2011, has taken a harder line regarding his country's claim on the territory.

The UK has made clear that it will not negotiate over sovereignty as long as Gibraltar's people want to remain British.

An FCO statement added: "Our differences with Spain on Gibraltar will be resolved by political means through our relationship as EU partners, not through disproportionate measures such as the border delays we have seen over the past week.

"We have many common interests with Spain and wish to continue to have a strong relationship at every level with the Government of Spain.

"In the meantime, we will be seeking an explanation from Spain following reports that the Spanish government might target Gibraltar with further measures."