Jean-Jacques Aillagon, culture minister under Jacques Chirac, called for the change

A close confidant of the French billionaire who pledged €100 million towards the restoration of Notre Dame has called for such donations to be 90 per cent tax deductible.

Former French culture minister Jean-Jacques Aillagon made the suggestion before the flames in the cathedral had been extinguished.

His suggestion came as his close friend François-Henri Pinault, who owns the firm behind Gucci and Yves Saint Laurent and is married to Salma Hayek, pledged the nine-figure sum to help 'completely rebuild' the Gothic monument.

Mr Aillagon has long been a close advisor of Mr Pinault's and now manages the Pinault Collection, the Pinault family's vast art collection.

Were the government to enact the policy, French taxpayers rather than the wealthy donors would foot most of the bill for repairs.

Ninety per cent of the sum donated would be taken off the wealthy individual's tax bill, leaving the Exchequer significantly out of pocket and needing to make up the shortfall from general taxation or by cutting spending.

French billionaire Francois-Henri Pinault and his wife Salma Hayek at the Cannes Film Festival. Mr Pinault pledged E100m towards the restoration of Notre Dame, while the man who runs his art collection called for such donations to be 90% tax deductible

Former culture minister Jean-Jacques Aillagon sent a two-part tweet calling on Parliament to pass a special law making 90% tax deductible 'the donations which will be made' to the restoration of Notre Dame

Twitter reaction was overwhelmingly negative in response to the suggestion, with one user replying: 'So in effect, the taxpayer will pay most of the donation and the very wealthy get the glory.'

Another said he would prefer a national subscription to pay for repairs with each giving what he could afford.

François-Henri Pinault is chairman and CEO of Kering, the French-based luxury group behind Gucci, Balenciaga, Yves Saint Laurent and other world-renowned brands.

He said in a statement that he plans to pay 100 million euros through his family's investment firm, Artemis, for any work that needs to be done following Monday's catastrophic fire.

Francois Pinault and Jean Jacques Aillagon at the 'Sigmar Polke' Exhibition opening at Palazzo Grassi in Venice in April 2016

Smoke is seen around the alter inside Notre Dame cathedral on Monday evening. Miraculously the cross and altar managed to survive the inferno

Firefighters tackle the blaze on Monday evening as flames and smoke rise from the Notre Dame cathedral as it burns in Paris

He said: 'This tragedy impacts all French people' and 'everyone wants to restore life as quickly as possible to this jewel of our heritage.'

He hoped the money will help church officials 'completely rebuild Notre Dame,' he added, after French president Emmanuel Macron vowed to do so earlier in the day.

There is no suggestion Mr Pinault has requested or backs any change to the tax law.

Regardless of any proposed tax changes, donations to rebuild Notre Dame have nonetheless exceeded 650 million euros as France's richest man pledged 200 million euros (£170m) towards the restoration after Monday night's inferno.

Bernard Arnault of luxury goods group LVMH doubled the 100 million euros pledged by Francois-Henri Pinault.

Other heavyweight donors include the Bettencourt family - owners of cosmetics giant L'Oreal - who have given 200 million euros and the French oil giant Total who donated 100 million on Tuesday.

Anne Hidalgo, the Mayor of Paris, said she wanted to organise an 'an international conference of donors' to welcome 'experts who are able to raise funds.'

Specialised craftsmen and rare materials are expected to be needed to restore the monument, which welcomes more than 13 million visitors each year - an average of more than 35,000 people a day.

The head of a French lumber company told FranceInfo radio that it was ready to offer the best oak beams available to rebuild the intricate lattice that supported the now-destroyed roof, known as the 'Forest'.

'The work will surely take years, decades even, but it will require thousands of cubic metres of wood. We'll have to find the best specimens, with large diameters,' Sylvain Charlois of the Charlois group in Murlin, central France, told the radio station.

The United Nations' Paris-based cultural agency UNESCO has also promised to stand 'at France's side' to restore the site, which it declared a world heritage site in 1991.

'We are already in contact with experts and ready to dispatch an urgent mission to evaluate the damage, save what can be saved and start elaborating measures for the short- and medium-term,' UNESCO's secretary general Audrey Azoulay said in a statement Tuesday