The Prince of Wales will be among guests at the service marking the reopening of Notre Dame Cathedral.
Prince William will be at ceremony in Paris which will be attended by around 50 heads of state and official representatives.
The heir to the throne is attending at the request of the government.
King Philippe and Queen Mathilde of the Belgians have also already confirmed their attendance as has the President elect of the United States, Donald Trump.
Other royals are expected among the 1,500 guests at the cathedral with Paris with reports that King Felipe VI of Spain will also be there.
The official reopening takes place five years after the medieval building was hit by a devastating fire. Thousands of hours of work and hundreds of people have been involved in restoring the cathedral.
The process of reopening Notre Dame will begin when Laurent Ulrich, the Catholic Archbishop of Paris, bangs on the doors with his crozier which has been created by Sylvain Dubuisson from charred pieces of wood that fell from the ceiling when the cathedral caught light.
Royalty and official guests are all invited by the President of France, Emmanuel Macron, who is currently under severe pressure after the new government fell in recent days.
There have also been complaints about access to the reopening of Notre Dame with security cordons put in place that will only allow guests and long term residents of the Ile de la Cite into the area. All shops in the tourist hotspot will be closed for the weekend leading to some complaints.
