Hundreds of millions of dollars have been pledged as part of the effort to rebuild the fire-ravaged Notre Dame Cathedral.

Rather than focusing on what was lost in the devastating fire only hours earlier, billionaires and corporations had already pledged huge figures to help restore the world-famous landmark on the banks of the Seine River.

The world’s third-richest man and Louis Vuitton chief executive Bernard Arnault promised €200 million euros ($316 million) via Twitter for the rebuild.

Francois-Henri Pinault, who is best known as the husband of actor Salma Hayek and the CEO behind French luxury fashion group Kering –which includes Gucci, Yves Saint Laurent, Balenciaga, Alexander McQueen and Bottega Veneta among its brands – pledged €100 million euros.

“This tragedy is striking all the French people, and beyond that, all those attached to spiritual values,” Mr Pinault said.

“Faced with this tragedy, everyone wishes to give life back to this jewel of our heritage as soon as possible.”

Hours later, the French oil and gas company, Total, announced another €100 million ($157 million) contribution, further fuelling the outpouring of sorrow that resulted in more than 300 fund-raising campaigns of various sizes being established on crowdsourcing website GoFundMe, by Tuesday night, Australian time.

Earlier on Tuesday, Prime Minister Scott Morrison scotched the idea of Australian taxpayers helping to foot the bill for the rebuild, saying the French and the Catholic Church can pay for it themselves.

Mr Morrison dismissed a suggestion by his predecessor Malcolm Turnbull that the government should establish a charitable fund for people who wanted to donate to restoration efforts.

“I’m sure that President [Emmanuel] Macron is able to deal with this – as is the Catholic Church – and, if individual Australians want to do something, well, it’s a free country – they can do whatever they like,” he told reporters in the Victorian Surf Coast town of Torquay.

Opposition Leader Bill Shorten also suggested Australians should help, adding that the cathedral “belongs to the world”.

Mr Shorten noted the “brooding, gothic cathedral” had been an important landmark in the days before GPS when he visited Paris as a young backpacker, and again during early morning runs on a more recent visit.

“Notre Dame doesn’t just belong to Paris or France, it belongs to the world,” Mr Shorten said.

“I think we, all of us who’ve enjoyed that architecture, that history, we too should perhaps rally around and help Paris and Notre Dame.”

The massive fire gutted and destroyed the roof of Notre Dame, but firefighters say they have saved the shell of the stone structure from collapse.

Unfortunately, Notre Dame’s 90-metre medieval spire could not be saved and crashed to the ground, drawing gasps and moans of disbelief from onlookers.

Thankfully, the cathedral’s medieval stone vaults may have saved the structure from complete devastation – just as it had survived revolution, two world wars and other threats since being built 850 years ago.

Dr Robert Bork, an architectural historian at the University of Iowa, told the ABC that the vaults acted as a buffer for the fire after it burned through wooden structures.

“The vaults are designed to be in dialogue with the buttressing system of the building … and if [Notre Dame] didn’t have them, the buttresses would have just had brick walls and in cases where you just have a timber roof building and the roof burns off, frequently those walls will collapse,” Dr Bork said.

The New York Times reports the fire appears to have been an accident, with Paris prosecutor Rémy Heitz saying: “Nothing at this stage suggests a voluntary act”.

Mr Heitz said that nearly 50 investigators were working to determine the cause of the fire, but that “it will be a long and complex investigation”.

No fire was found after the first alarm was triggered at 6.20pm. But a fire was discovered in the wooden framework of the attic when a second alarm sounded at 6.43pm.

Emergency officials inspected the structural integrity of the building on Tuesday, hopeful it will not collapse.

Heartfelt tributes have flowed from around the world after flames ripped through the historic landmark on Tuesday morning, Australian time.

The news of the cathedral fire surfaced just as one of Islam’s holiest sites also suffered fire damage in Jerusalem almost simultaneously.

Footage showing smoke and fire emerging from the revered Al-Aqsa Mosque compound in the structure known as the Marwani Prayer Room, or Solomon’s Stables, could be seen on social media.

The Palestine News Agency reported that “the fire broke out in the guard’s room outside the roof of the Marwani Prayer Room, and the fire brigade of the Islamic Waqf handled the matter successfully”.

طواقم الإطفاء تخمد حريقاً اندلع على سطح المصلى المرواني في المسجد الأقصى. pic.twitter.com/CVx8X7nx4N

— المركز الفلسطيني للإعلام (@PalinfoAr) April 15, 2019