Fire swept through the iconic building in April 2019, destroying much of the roof and the spire.

The spire, which was 93 metres high, collapsed as a result of the blaze.

"The return of the spire in the Paris sky will be the symbol that we are winning the battle of Notre-Dame," said Gen. Jean-Louis Georgelin, the army general in charge of the rebuild, to Associated Press.

Preliminary work to stabilise the site was completed in 2021, so that restoration could begin on the cathedral interior without the danger of damaged scaffolding collapsing inside.

Originally, French President Emanuel Macron had expressed hope to Paris 2024 counterpart Tony Estanguet that work would be completed in time for the Games.

But the December 2024 date confirmed by Georgelin has been given for formal worship, almost three months after the Closing Ceremony of the Paralympics on September 8.

Within a few days of the fire, International Olympic Committee President Thomas Bach pledged a donation of €500,000 (£432,000/$562,000) towards the restoration.

French Culture Minister Rima Abdul Malak had expressed her confidence that the work would be complete in time for the Games last year.

A free exhibition about the work and restoration of the cathedral has opened in an underground area in front of the building.

It includes some remains from the fire and artwork from the cathedral.

This will remain open throughout the Olympics and Paralympics, with a virtual reality presentation on the cathedral which will enable visitors "to live what could be this experience of visiting Notre-Dame in a brand new way".