The government of Portugal has asked France’s Vinci to submit a proposal for the construction and operation of a new international airport for Lisbon, the Aviacionline website reports.

Portugal wants the €9bn airport to be financed privately on a public-private partnership basis, without relying on public funds.

The move comes eight months after talks began between the two sides .

The airport is planned for the municipality of Alcochete, on the other side of the Tagus River from Lisbon.

The government is hoping to complete the first phase by 2034, at which point work can begin on dismantling Humberto Delgado airport, which is operating at peak capacity.

The first phase will have two runways, each four kilometres long, capable of accommodating all types of aircraft.

Subsequent phases will add two more runways, and will increase Alcochete’s capacity to 100 million by 2050, putting it in the global first division of airports.

If Vinci accepts the proposal, it will carry out the work under its ANA subsidiary, which has been managing Humberto Delgado, and nine other airports in Portugal, since 2012 under a contract that extends to 2062.

ANA submitted its initial documentation in December, which Portugal’s Ministry of Infrastructure said was in alignment with its plans to build the airport with no contributions from the state budget.

ANA now has up to 36 months to work through its construction plans. The government has stressed its willingness to discuss adjustments to the project’s specifications, financing models and risk-sharing provisions.