ATHENS (Reuters) - Greece lifted COVID-19 restrictions on Sunday for foreign and domestic flights, its civil aviation authority said, ahead of the summer tourism season that officials hope will see revenues bouncing back from the pandemic slump.

       To fly in or out of the country, travellers were previously required to show either a vaccination certificate, a certificate saying they had recovered from coronavirus or a negative test.

       From May 1, passengers and crew will need only to wear a face mask, the civil aviation authority said.

       The summer tourism season typically begins after the Greek Orthodox Easter, which was on April 24. Greece is expecting high numbers of visitors this year, with officials predicting revenues reaching 80% of 2019 levels. That was a record year before the pandemic brought travel to a halt.

       With infections waning, restaurants and retail shops returned to 100% capacity on Sunday, allowing customers in without proof of vaccination but with a mask.

       Greece has reported 3,323,922 cases so far and 29,153 deaths from COVID.

       (Reporting by Angeliki Koutantou; Editing by Frances Kerry)