Brussels' Zaventem Airport departure hall has reopened to the public, 40 days after twin suicide attacks killed 16 people.

Belgium's prime minister Charles Michel reopened the hall, which is currently operating at 80% capacity, with 111 check-in desks out of 180 operational.

Temporary structures outside the airport erected after the coordinated attacks on March 22 remain in service to control passengers and luggage before they enter the departure hall.

A total of 32 people died and more than 300 were injured during the suicide attacks at Zaventem Airport and Maalbeek metro station. The bombings were the deadliest act of terrorism in the country.