FRENCH billionaire Francois-Henri Pinault said he is pledging to donate 100 million euro (£86 million) to rebuild Notre Dame as the cathedral is a "symbol of spirituality and our common humanity".

Speaking to BBC Radio 4's Today programme, the businessman said he expects others to follow suit as "it has to be a collective endeavour" to renovate the Parisian landmark, saying that "everyone with means and recourse should participate".

He said it was a "shock" to see the building on fire on Monday night, adding: "We need to rebuild collectively this part of our history, of our culture, so it's an urgent, urgent need to move forward, so I decided to unlock a very important amount of money to do that."

Asked if others from around the world could join him in donating money, he said: "Everyone is welcome, it goes beyond France, it's a symbol of our culture, a symbol of spirituality and our common humanity."

Pinault said the money, which comes from his family's personal wealth and not his retail empire Kering, comes with no strings attached or "ownership" as to how it is used to repair Notre Dame.

Pope Francis is praying for French Catholics and the Parisian population "under the shock of the terrible fire" that ravaged Notre Dame.

Vatican spokesman Alessandro Gisotti said on Twitter that the pope "is close to France" and that he is offering prayers "for all those who are trying to cope with this dramatic situation".

Earlier, the Vatican expressed "shock and sadness" at the fire that caused extensive damage to "a symbol of Christianity in France and in the world".

Paris' deputy mayor said Notre Dame's organ, one of the biggest and most famous in the world, remains intact after the fire.

Emmanuel Gregoire told BFMTV that a plan to protect the cathedral's treasures had been rapidly and successfully activated.

The organ dates to the 1730s and was constructed by Francois Thierry. It boasts an estimated 8,000 pipes.

Gregoire also described "enormous relief" at the salvaging of pieces such as the purported Crown of Christ.

French politician Nicolas Dupont-Aignan praised businessmen Bernard Arnault and Francois-Henri Pinault for "setting an example" by pledging millions of pounds to repair the building.

Speaking to press in front of Notre Dame, he said: "All the Parisians who have gathered on the banks have demanded an inquiry to understand what happened - is it an accident and why such an accident?

"How can all of this burn? It's terrible - or, is it more serious?

"I think the French are asking themselves this question."

He added: "The French want to know what happened and we have to give them the truth."

Dupont-Aignan, who founded the political party Debout la France in 1999, added: "The state will need to devote millions, and it will take decades [to repair] and when we look at the damage, it is a tragedy.

"What can we do to understand how that happened and what can we do to prevent it happening to other monuments in our country?"

He said it would be a "good thing" if the process of rebuilding Notre Dame became a means of uniting France.

Labour leader Jeremy Corbyn said the fire at Notre Dame was "very, very sad".

He said: "I've been in Notre Dame cathedral several times. It's absolutely stunning and beautiful and you can see the whole history of France before you there.

"You can see the majesty and beauty of that building and to see it destroyed is devastating, I think for everybody in Paris and indeed around the world, because you see beautiful buildings like that and think of the beautiful buildings we've got in this country. If any of those were destroyed in fire how would we feel about it?

"Well done on the firefighters on at least managing to contain it in the end, but sadly the spires have gone and I note that President Macron wants to rebuild the whole cathedral. I hope that happens."

He said the blaze was a warning for MPs about the state of the Palace of Westminster and major work would have to be done.

He said: "The state of the building is very poor in Westminster and a fire risk is obviously huge with a building that has so much wood within it."

Egypt's top Muslim cleric has expressed sadness over the fire that destroyed part of the famous Notre Dame cathedral in Paris, describing it as an "historic architectural masterpiece".

Sheikh Ahmed al-Tayeb, the grand imam of Al-Azhar, the Sunni Muslim world's seat of learning, wrote on Facebook: "Our hearts are with our brothers in France."

The Archbishop of Canterbury Justin Welby tweeted an image of the fire-damaged cathedral with the Bible passage: "The light shines in the darkness, and the darkness has not overcome it.' (John 1:5) #NotreDame."