Airport controls would last longer, until 29 March, when airlines switch to their summer schedule, as to allow them to re-organise terminals and boarding facilities to meet the Schengen requirements.

French interior minister Michele Alliot-Marie, who chaired the EU meeting, said she was "particularly happy about this decision" and congratulated the Swiss authorities.

Swiss Justice Minister Eveline Widmer-Schlumpf said the accord could help boost tourism and improve procedures in dealing with asylum seekers from other Schengen states.

Police would also be better equipped to track cross-border criminals by using the Schengen Information System, a data bank used by many European countries with information on wanted persons and stolen goods.

The Schengen passport-free zone includes all EU member states except Cyprus, Britain and Ireland, who opted to stay out, as well as Romania and Bulgaria who still have to qualify, and hope to join by 2011.

The area was originally created by France, Germany, Belgium, the Netherlands and Luxembourg in 1985 near the Luxembourgish town of Schengen, and put into practice in 1990. Switzerland voted in a 2005 referendum to join the Schengen area.

Referendum could reinstall borders

But the Swiss could still reverse this decision in a fresh referendum scheduled for February, on the subject of extending free movement of workers to EU's newest members Romania and Bulgaria.

EU justice commissioner Jacques Barrot said that if the referendum proved negative, "it would involve a real problem and would probably mean that the presence of Switzerland in the Schengen area would be interrupted."

Czech interior minister Ivan Langer, speaking on behalf of the upcoming Czech EU presidency, encouraged the Swiss to "share the free movement," stressing that the Schengen area brings "beautiful benefits" as experienced by his country, which joined the zone 12 months ago.

Right-wing parties in the Swiss parliament have managed to obtain the necessary signatures to hold a referendum on the government's decision to extend the freedom of movement to Romania and Bulgaria.

Change of heart

The Swiss People's Party, which holds the most seats in the parliament, had a sudden change of line at the end of October, saying that it would also fight the extension of the labour agreement with the EU.

According to the faction's president, Toni Brunner, the party had always spoken out against the extension of the free movement of people deal with Bulgaria and Romania.

"We must say no to the package presented by parliament," he said last month, despite prominent party figures such as former justice minister Christoph Blocher, having previously pleaded against a popular vote.

Swiss voters will have the final say on 8 February, with three of the four parties in government, as well as the business lobby, recommending they accept the EU terms.