Over the next two years a ground-breaking decision by the council of ministers and the European Parliament will result in the biggest release of information held by governments to the public and the media since the creation of the European Union.

All 27 EU countries will disclose data revealing details of some €100bn given in subsidies by the Eurotaxpayer every year to farmers, food companies, industrial regeneration schemes and the fishing industry, from the Black Sea resorts in Bulgaria and Romania to the Canary Islands and Madeira.

The decision is the result of a rare example of journalists cooperating with each other across Europe to bring pressure on the governments of member states, using national freedom of information laws.

The data that will be released next year and in 2009 has been among the secrets most strongly guarded by national governments, who have used privacy and data protection laws to prevent people finding out the main recipients of the Euro largesse. The reason - as has become clear as the information has dribbled out - is to protect from unwanted publicity not poverty-stricken hill farmers but huge multinationals such as Tate & Lyle and the Danish Arla group (which owns Express Dairies), powerful politicians, and royals from the Queen and Prince Charles to the Grimaldis in Monaco. For they are emerging as the biggest beneficiaries under the information already released.

The idea that all this should become public originated in 2000 - not from a journalist but from a Labour special adviser, Jack Thurston, who worked for Nick Brown, then agriculture minister. One afternoon, fed up with a rather tedious EU agriculture negotiation, Brown demanded from his permanent secretary, Sir Richard Packer, a list of the top 20 people getting all these EU subsidies. After much trepidation Sir Richard produced the list and allowed the minister to glance at it for 10 minutes. Thurston remembers looking over his shoulder and seeing the royals and multinationals heading the list.

When Brown asked to take it away, the request was refused and he was warned that to publish such information breached the Data Protection Act. After Thurston left his job he wrote a pamphlet for the Foreign Policy Centre think-tank challenging the need for the subsidies and calling for the details to the published. At the same time, a Danish journalist, Nils Mulvad, used a provision under the Danish freedom of information act to demand the release of documents sent to the tax authorities that listed EU subsidy payments. At the third attempt, in 2004, he won his case and Denmark became the first country in the EU to release subsidy payment data. Last year he was voted European Journalist of the Year in European Voice's awards.

Three months after the Danish ruling Britain's FOI Act became operational on January 2, 2005. On the day the act became law the Guardian joined the Foreign Policy Centre to demand the release of all subsidies in England and Northern Ireland (Scotland and Wales had separate jurisdiction). While the Guardian was publicly demanding the information, Thurston was using his Labour connections to press Margaret Beckett, then agriculture secretary, and Larry Whitty, the farms minister, and advisers to Gordon Brown, to concede. The government agreed and Britain became the first big member of the EU to release the information.

By May through the offices of the German Marshall Fund, another think-tank, a meeting in Brussels united journalists from Britain, Denmark, Sweden, Holland, Germany and Spain, among others to share information. What followed was the establishment of the website farmsubsidy.org, which publishes articles from journalists revealing grants as each country has been pushed into naming who gets the cash.

Some countries fell after spectacular events - Holland decided to release the information after the Dutch agriculture minister, Cees Veerman, was exposed for not revealing to Parliament that he was taking EU subsidies for farms he owned in the Dordogne. Others, like Slovenia, volunteered to release everything when they joined the EU. Journalists in Sweden, Finland and Norway, which is not even an EU member, have forced their governments to release data. And transnational journalism meant that Arla was revealed to have received more in EU subsidies through Denmark, Sweden, the United Kingdom and Holland, than from profits it made.

It was this background that led the EU Commission to go for releasing details of every subsidy it gave. By the time it agreed to take such a historic step, countries were falling like dominoes as journalists forced the release of information under FOI laws. Germany is the latest.

Thurston says: "Journalists have been central. Without them all we would have is raw data. It is journalists, who have the local knowledge about the people and companies who receive the money, who turn the information into stories which people can relate to - therefore making government more accountable to the people who pay for these subsidies."