EUROPEAN UNION
European Commission head Jean-Claude Juncker congratulated the pro-EU Macron and wished him "good luck" in the run-off, Juncker's spokesman tweeted.
"To see the flags of #France and the EU greet the result of @emmanuelmacron, it's the hope and future of our generation," tweeted EU foreign policy chief Federica Mogherini.
Michel Barnier, the European Commission's chief negotiator on Britain's withdrawal from the EU, hinted at concerns Le Pen could lead France away from the bloc.
"Patriot and European, I will put my trust in Emmanuel Macron on May 7. France must remain European," the Frenchman tweeted.
RUSSIA
Kremlin spokesman Dmitry Peskov said Russia "respects" the result, and is "in favour of building good and mutually beneficial relations".
Russia has appeared as a keen backer of Le Pen, who met President Vladimir Putin in a surprise visit to Moscow ahead of the vote.
GERMANY
Chancellor Angela Merkel's spokesman wished Macron "all the best for the next two weeks".
"It's good that Emmanuel Macron was successful with his course for a strong EU and social market economy," Steffen Seibert said in a tweet.
Foreign Minister Sigmar Gabriel expressed confidence that the 39-year-old would be France's next president.
"I'm sure he will sweep away the far-right, rightwing populism and the anti-Europeans in the second round," Social Democrat Gabriel said in a video posted on Twitter during a trip to Amman.
Writing on Twitter, he added: "I'm glad that @EmmanuelMacron is leading the field. He was the only truly pro-European candidate."
AUSTRIA
The head of the Austrian far-right FPOe, Heinz-Christian Strache, congratulated Le Pen on her "historic success".
"Europe's patriotic spring can celebrate another success and step forward... The old established parties and their discredited representatives will gradually disappear into insignificance all across Europe. They have been ruining Europe for years!" he said on Facebook.
Strache said that because "established French parties" were backing Macron, it would be a "wonder" if Le Pen won the second round.
"But the system, like in Austria, is on the brink. It is just a question of time. More and __more citizens have had enough of the system politicians responsible for the current disaster."
BRITAIN
Former Conservative finance minister George Osborne, recently appointed editor of London's Evening Standard newspaper, hailed a good result for the centre.
"Congratulations to my friend @EmmanuelMacron. Proof you can win from the centre. At last, the chance for the leadership that France needs," he tweeted.
DENMARK
Prime Minister Lars Lokke Rasmussen expressed cautious optimism that former banker Macron would emerge victorious over Le Pen.
"Congratulations @EmmanuelMacron. We should await the final election, but Europe needs an openminded and reform oriented France => Good luck!"
NORWAY
Norwegian Foreign Minister Borge Brende, whose country is not a member of the European Union, tweeted: "We need __more not less cooperation in #Europe."
THE NETHERLANDS
Geert Wilders, Dutch MP and leader of the anti-Islam anti-immigrant Freedom Party, swung behind Le Pen, welcoming the result as a "bright day for patriots in France and elsewhere who want more national sovereignty and less EU and immigration.
"I have just sent her my sincere congratulations. Now on the way to a vigorous second round, I am hoping for a President Le Pen."