Workers are refitting the construction site at fire-damaged Notre Dame Cathedral to protect staff from coronavirus and allow clean-up efforts at the Paris landmark to resume.

More than a year after the blaze, the coronavirus outbreak caused a setback in the restoration of the cathedral, with work halted in mid-March when France imposed strict confinement measures.

On Monday, workers began to re-arrange the construction site to make it virus-safe, according to an official with the state agency overseeing the project.

The site is hidden from the public by high barriers.

That includes re-arranging showers and cloakrooms to allow more distance between workers, and installing a place to eat because restaurants in France are currently closed, Notre Dame rector Monsignor Patrick Chauvet told reporters outside the site.

He said most workers will stay in nearby vacant hotels so they will not have to take public transportation.

He said the priority will be taking down 250 tons of scaffolding that had been installed for a prior renovation project and was badly damaged in the blaze. The unstable scaffolding further endangers the cathedral.

"It's a difficult job. It requires the climbers to be calm," he said. "We can't have Covid there to cause them stress."

The clean-up work itself is scheduled to start gradually resuming next week.

Despite the delay, the general in charge of the reconstruction said he still wants to stick to ambitious plans to hand the cathedral back to the Catholic Church in 2024, when Paris is set to host the Olympics.