Thousands of workers who cross daily from Spain into Gibraltar have become the latest pawns in the simmering political dispute between Spain and Britain over sovereignty of the Rock.
Around 70 fishermen and their families from the southern Spanish port of La Linea blockaded the frontier, causing delays of up to five hours at the border. The latest incident erupted a week ago after Gibraltar coast guards detained the Pirana, a small Spanish trawler, for fishing too close to Gibraltar.
It was just another of the regular confrontations in Spain's battle to regain sovereignty over the 2.5 sq mile Rock and its 28,000 inhabitants.
Gibraltar, the last colony in Europe, has been a long-standing bone of contention between Britain and Spain, and is the main stumbling block in otherwise harmonious relations between two European allies.
It was ceded to Britain in 1713 under the Treaty of Utrecht, and under the terms of the treaty must revert to Spain if it is ever de-colonised - a possibility Gibraltarians refuse to accept. In 1969 the border was closed, and not reopened until 1983. But far from achieving its aim of starving out the inhabitants by making life impossible, the closure created a siege mentality which drew them closer together and created a sense of Gibraltarian nationality.
For centuries the local fishermen fished off the Rock until a 1991 ordinance restricted the use of nets within a three-mile limit. Last October, without the approval of the Gibraltarian local government, the British Foreign Secretary, Mr Robin Cook, reached a verbal agreement with his Spanish counterpart, Mr Abel Matutes, lifting these restrictions, permitting local fishermen to fish up to 300 metres from the shore.
Gibraltar's answer was to seize the Pirana, sparking off the latest crisis, with violent clashes between the fishermen and Gibraltarians.
Instead of resorting to official government channels, the fishermen decided to negotiate directly with the Gibraltar authorities and began their own talks with the Chief Minister, Mr Peter Caruana, a moderate, British-educated barrister. They reached a mutually acceptable agreement without prior reference to Madrid or London.
Mr Matutes, the normally diplomatic Spanish Foreign Minister, has been uncharacteristically outspoken over the affair. Since Spain does not recognise Gibraltar, or its government, he refuses to recognise any agreement made with the Gibraltarians.
"If they care to paper their bathrooms with the agreement, they are welcome," he said, although he is expected to have a telephone conversation with Mr Cook to discuss the latest crisis. He warned that Spain would step up its restrictions at the border, creating further problems for the 11,000 people who cross each day.
Local inhabitants complain that Spain is imposing a process of harassment aimed at making their life on the Rock impossible. Gibraltar passports are not recognised by Spain, and more recently it has begun to refuse to accept legal documents registered in Gibraltar.
Mr Stephen Bullock, a lawyer based in Gibraltar who was educated at Trinity College Dublin, said he was worried about the consequences of such restrictions on the business world. "Thousands of foreign residents who live on the Spanish Costas have powers of attorney and other papers registered here. It will cause chaos if Spain refuses to honour them."
The British Prime Minister, Mr Blair, said yesterday: "We are in fact working very closely with the Gibraltar authorities and, as a result of that, the Chief Secretary in Gibraltar has made arrangements in order to bring this dispute to an end which we very much hope there will be proper progress upon."
The Basque separatist group, ETA, has sent a letter to some journalists, accusing them of being anti-Basque and warned them that the Basque people will never forget or forgive.