LISBON, Portugal (AP) — Portugal's government has unveiled a 1.1-billion euro ($1.26 billion) plan to expand Lisbon's current airport and build a second one, even though an environmental impact study that could thwart its ambitions isn't finished.

National airports operator ANA is footing the bill to adapt a military airfield in Montijo, 30 kilometers (18 miles) by road from Lisbon. It aims to handle around 50 million passengers a year from 2022.

Authorities say an environmental study will be ready by April. Critics accuse the government of rushing into the project because a general election is due in October.

Officials said Tuesday the airports company will also pay for the expansion of the Humberto Delgado Airport in the capital. With around 29 million passengers a year, it is at full capacity.