Portugal unveiled plans on Tuesday to go ahead with construction of a new EUR3 billion (USD$3.5 billion) international airport, which is criticized by some analysts as too costly for the cash-strapped country.

Underscoring the airport's importance, the Socialist government held a full-day presentation on its plans that included the presence of Prime Minister Jose Socrates.

Public Works Minister Mario Lino said the government had made a decision to go ahead, although he cited a long-term timetable for construction to get underway.

He said a public tender would be launched to build the international airport at Ota, about 50 km north of Lisbon, and that work should start before 2010.

The building of a new international airport has been discussed for at least a decade. A decision to go ahead has been repeatedly delayed because of a lack of cross-party political agreement and the high cost.

"The studies carried out conclude that the Ota solution was the best, and the decision (to go ahead) was taken by the government, considering that the project has great importance for the country," Lino said at the conference.

He said the government would bear 10 percent of the cost. Work needs to start before 2010 to let Portugal take advantage of funding assistance from the European Union.

The new airport, which would be operational as of 2017, would create 50,000 new direct and indirect jobs, Lino said. The project will also require a rail link to Lisbon and new roads.

Lino said that under this government's plan, Lisbon's Portela Airport would be decommissioned altogether.

Lisbon politicians and businesses have strongly opposed shutting down the city's airport if Ota were built because of worries about lost tourist traffic.

Some analysts have criticized the project, saying Portugal can not afford it. Portugal, the poorest country in western Europe, has the widest budget deficit in the euro currency zone.