Lisbon is to have a new international airport after more than 35 years of debate about the site.

Portugal’s prime minister Jose Socrates has identified Alcochete on the south bank of the Tagus river as the government’s preferred option for the airport, to be built at a cost of €5 billion.

Only last year ministers suggested the airport would be at Ota, 50kms from the city centre. However, discussion about the site has gone on since the early 1970s. The final go-ahead will depend on a public consultation.

Lisbon’s existing international airport at Portela, in a built-up area of the city, is undergoing expansion due for completion in 2010.

The government has been accused od underestimating the cost of the new airport, put privately at up to €9 billion.