French President Emmanuel Macron praised on Friday the more than 1,000 craftspeople who helped rebuild Paris' Notre-Dame Cathedral in what he called "the project of the century", five-and-a-half years after fire gutted the Gothic masterpiece.

French President Emmanuel Macron has told workers who revived Paris' iconic, fire-ravaged Notre Dame cathedral, that they "achieved what was thought impossible."

France on Friday showed off to the world the gleaming restored interior of the Notre Dame de Paris cathedral, just over a week before the 850-year-old medieval edifice reopens following painstaking restoration after a devastating fire.