World leaders mourn the Notre-Dame fire.

AFP - The world mourned helplessly the fire that destroyed Notre-Dame Cathedral in Paris on Monday (15), a "symbol of France" and European culture, according to German Chancellor Angela Merkel, while US President Donald Trump described the event as "horrible to see".

Trump was one of the first heads of state to speak out, calling for immediate action in a tweet as TV images showed the horrific episode live.

"It's so horrible to see the huge fire at Notre-Dame Cathedral in Paris. Maybe they could use tanker planes to put it out. Action must be taken quickly!" Trump tweeted.

Major US news channels altered their programming to broadcast live images of the fire. Melania Trump, the First Lady of the United States, said she was "heartbroken" for Parisians as she watched the flames engulf the cathedral.

Former President Barack Obama said that it is human to grieve the losses "but it is also in our nature to rebuild for tomorrow, with as much strength as we can."

"These horrific images of Notre-Dame in flames are heartbreaking. Notre-Dame is a symbol of France and of our European culture. Our thoughts are with our French friends," tweeted Merkel's spokesman, Steffen Seibert.

German Foreign Minister Heiko Maas had earlier stated that the fire was also striking at the heart of the German people.

Major German news channels also broadcast live images of the incident.

The same thing happened in Italy, where the head of government, Giuseppe Conte, lamented what he called a "blow to the heart of the French and Europeans."

The Spanish head of government also highlighted the blow to European civilization.

"The Notre-Dame fire is a catastrophe for France. It is also for Spain and for Europe. The flames are destroying 850 years of history, architecture, painting, and sculpture. It will be difficult to forget. France can count on us to recover the grandeur of its heritage."

UNESCO also immediately offered its assistance in restoring this priceless heritage, according to its Director-General, Andrey Azoulay. The cathedral was declared a World Heritage Site in 1991 by the Paris-based organization.

In New York, UN Secretary-General António Guterres said he was "horrified" by the destruction of a "unique jewel of world heritage, which has reigned in Paris since the 14th century."

Costa Rican President Carlos Alvarado said on Twitter that his country stands in solidarity with France "in the face of the devastating fire" that destroyed "an icon of the history of that nation and of Europe."

Colombian Foreign Minister Iván Duque and Peruvian Foreign Minister Néstor Popolizio also sent messages of solidarity, as did the Mexican Foreign Ministry.

Also from the United States, where he is on a visit, the president of Ecuador, Lenin Moreno, said that he viewed with "infinite sadness" the images of the fire "of a monument that is a world heritage site".

"Notre-Dame Cathedral belongs to everyone. We must help preserve the memory and history of the world. We are losing a treasure, a page of world culture."

President Jair Bolsonaro also lamented the damage to Notre-Dame.

"On behalf of Brazilians, I express my deepest sorrow for the terrible fire that is ravaging one of the greatest symbols of Christian and Western culture and spirituality, the Notre-Dame Cathedral in Paris. In this dark moment, our prayers are with the French people," he tweeted.

In a message released before that of the Vatican itself, the Anglican Church of England announced it was praying for the firefighters and first responders battling the flames.

British Prime Minister Theresa May sent her "thoughts" to the people of France, and the Mayor of London said it broke his heart to see Notre-Dame in flames.

Pope Francis has not commented, but a Vatican spokesman expressed his "disbelief" and "sadness" shortly afterwards.

"We express our closeness to French Catholics and the people of Paris. We pray for the firefighters and all those who are doing everything possible in the face of this dramatic situation."

The Catholic Church in the Holy Land also reported that it is praying that the fire that devastated Notre-Dame Cathedral was "unintentional" and expressed solidarity with the Church in France.

"We pray that there are no injuries, that the fire was not intentional, and that the church suffers as little damage as possible," he said in a statement released from Jerusalem.

"We express our solidarity with the Church in France," the text adds.

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