Cafes and restaurants with outdoor seating reopened on Saturday after almost seven months, but theatres and cinemas have remained closed.

"We have taken giant steps forward," in the vaccination campaign, Prime Minister Alexander de Croo said, justifying the long-awaited easing.

By June 9, Belgium expects to have vaccinated 80 percent of people over 65 and vulnerable people, he said. 

It will be necessary to "keep the situation under control in the intensive care units" where the number of patients should not exceed 500, De Croo added. 

There are currently around 700 patients in intensive care, a figure that has been falling steadily for the past two weeks. 

The measures also include loosening remote working rules by allowing one in five workers to return to the office in four weeks' time. 

Rules around gatherings will be eased too, with four guests allowed inside people's homes instead of two.

In Belgium, total infections since the beginning of the pandemic recently broke one million cases.

But even though cases have dropped over the past weeks, there was still a daily average of 2,936 in the past seven days.

Vaccinations have accelerated in the country since the end of March, with over 3.5 million of the population of 11.5 million having received at least a first dose.