French billionaire Francois-Henri Pinault, chairman and CEO of the international luxury group Kering, is pledging 100 million euros ($113 million) to help rebuild Paris’ Notre Dame Cathedral after a massive blaze ripped through the over 800-year-old church Monday, according to Agence France-Presse.

Pinault owns several high-end fashion brands, including Gucci, Yves Saint Laurent, and Balenciaga, and is the husband of actress Salma Hayek. Forbes pegs the Pinault family fortune at $35 billion.

A massive fire engulfed the upper reaches of the Notre Dame Cathedral as it was undergoing renovations Monday, threatening one of the greatest architectural treasures of the Western world as tourists and Parisians looked on aghast from the streets below.

The blaze collapsed the cathedral’s spire and spread to one of its landmark rectangular towers, but Paris fire chief Jean-Claude Gallet said the church’s structure had been saved after firefighters managed to stop the fire spreading to the northern belfry. The 12th-century cathedral is home to incalculable works of art and is one of the world’s most famous tourist attractions, immortalized by Victor Hugo’s 1831 novel The Hunchback of Notre Dame.

The exact cause of the blaze was not known, but French media quoted the Paris fire brigade as saying the fire is “potentially linked” to a $6.8 million renovation project on the church’s spire and its 250 tons of lead. The Paris prosecutors’ office ruled out arson and possible terror-related motives, and said it was treating it as an accident.

As the spire fell, the sky lit up orange and flames shot out of the roof behind the nave of the cathedral, among the most visited landmarks in the world. Hundreds of people lined up bridges around the island that houses the church, watching in shock as acrid smoke rose in plumes. Speaking alongside junior Interior minister Laurent Nunez late Monday, Gallet noted that “two thirds of the roofing has been ravaged.” He said firefighters would keep working overnight to cool down the building.

French President Emmanuel Macron pledged to rebuild the Notre Dame in a press conference, vowing to seek out the world’s foremost experts.

“I say this to you solemnly this evening: we will rebuild this cathedral. All together,” Macron declared. “And it is certainly a part of our destiny as France and our project for years to come.”

“We will call on the most talented people,” he added. “We will rebuild because it is what the French people expect, because it is what our history deserves. Because it is our profound destiny.”

The Associated Press contributed to this report.