Greek PM Alexis Tsipras joined international leaders on Monday evening in conveying his deep sorrow over the devastating fire at the landmark Notre Dame Cathedral in Paris.

In a Greek-language Tweet on Tsipras' account, the message reads: "... Not only is this a catastrophe for France, but for Europe's and the world's cultural legacy, @emmanuelMacron, we are by your side."

Greece's main opposition leader, Kyriakos Mitsotakis, also took to his Twitter account on Monday to express his shock over destructive blaze, watched lived around the world.

"The images of #NotreDame in flames are absolutely heartbreaking to watch. Notre-Dame is a historical and religious landmark of Paris, of France and of Europe. All our thoughts and prayers are with the French people tonight," he Tweeted in English.