Architects from around the world will have the chance to design the next Notre-Dame spire

As France mourns the damage to its 850-year-old Notre-Dame Cathedral, architects around the world have been given the chance of a lifetime.

A huge fire swept through the roof of the famed Notre-Dame Cathedral in central Paris on Monday evening, sending flames and huge clouds of grey smoke billowing Source: AAP

Architects from around the world - including Australia - will be asked to submit their designs for a new spire to sit atop the Notre-Dame Cathedral in Paris, after it toppled during a huge blaze on Monday. 

French Prime Minister Édouard Philippe announced the contest on Wednesday, saying the country would be looking for a "new spire that is adapted to the techniques and challenges of our era". 

The former 93-meter spire was the work of Eugene Viollet le Duc and only added to the 850-year-old building during a 19th Century restoration.

The spire ablaze before it collapsed on Monday. Source: AAP

"The international competition will decide whether a spire should be rebuilt, [and] whether the spire designed and built by Viollet le Duc should be rebuilt in the same way, identically," Mr Philippe said.

French President Emmanuel Macron has vowed the historic cathedral will be rebuilt "even more beautifully" within five years - a claim some experts believe is impossible.

The fire damage to the area where the spire once was. Source: AAP

"It's quite possible to do it [in five years] using multinational companies that work extremely fast, the way they build a reinforced-concrete skyscraper," Benjamin Mouton, chief architect at Notre-Dame until 2013, said.

Whether or not the new spire design mimics Viollet le Duc's masterpiece, one much-loved element looks set to return.

The copper statue of a cockerel that sat atop the spire has been recovered amongst the rubble. President of the French Building Federation Jacques Chanut tweeted a gleeful picture of architect Phillippe Villeneuve clutching the rooster. 

On Wednesday, Mr Phillippe said it was unclear how much the ambitious project would cost, but experts have given ballpark estimates in the hundreds of millions of euros.

Already some 850 million euros has been pledged, mainly from French billionaires and companies as well as the city of Paris and other authorities.

As the debate about how the rebuild should proceed begun, cathedral bells rang out across Paris on Wednesday evening - marking the exact moment the blaze broke out.

"Our beloved cathedral is on her knees" but she "will live again", she "will rise again", the Archbishop of Paris Michel Aupetit said during a mass at the church of Saint-Sulpice.