"There are very few moments in our lives where we have the privilege of witnessing history taking place. This is one of those moments," US President Barack Obama said in his remarks.
Obama led the world leaders in welcoming the violence-free revolution and said the Egyptian events were "irreversible" and asked the military to ensure transition to true democracy at the earliest.
"The people of Egypt have spoken," US President said, adding they would settle for nothing less than "genuine democracy".
UN Chief Ban Ki-moon praised Mubarak for bowing to the will of the people and taking a decision in the interest of Egyptian people.
Egypt`s neighbour Israel had no official response to the momentous development but unnamed officials were quoted by local press as expressing cautious optimism saying, "We hope that the peace accord will remain."
Israel`s hawkish Prime Minister Benjamin Netanyahu last week warned of an Iranian-style Islamist revolution in Egypt should Mubarak`s rivals, the Muslim Brotherhood, eventually succeed in taking over the reigns.
France, President Nicolas Sarkozy said, saluted Mubarak`s "courageous and necessary decision" to step down and hoped Egyptian people will continue their March to liberty.
German Chancellor Angela Merkel described Mubarak`s departure as historic change and said she hoped the next Egyptian government would continue to keep peace in the Middle East and respect agreement with Israel.
Welcoming the change, British Prime Minister said those who now run Egypt have a duty to reflect the wishes of the people.
Russian Foreign Minister Minister Sergei Lavrov said the shift of power should restore stability in the nation.
Spain also joined in calls for speedy electoral reforms.
Canadian Prime Minister Stephen Harper called for holding early free and fair elections and respecting human rights of all including minorities.
South African President Jacob Zuma lauded Mubarak for putting interest of Egyptians above his own.
In a statement, Australian Prime Minister Julia Gillard said, "Australia calls for constitutional reform and a clear timetable towards free and fair elections and a representative civilian government that ordinary Egyptians have been calling for."