U.S. President George W. Bush and British Foreign Secretary Jack Straw said they were praying for the Israeli leader, who is fighting for his life after a massive stroke yesterday.
Others were less charitable.
Iranian President Mahmoud Ahmadinejad was quoted by Iranian media as equating Sharon with a terrorist and hoping that the Israeli leader will die.
The Palestinian militant group Hamas echoed that sentiment, saying the Middle East would be better off without Sharon.
But while some celebrated in Gaza, Palestinian Prime Minister Ahmed Qorei said he hopes Sharon recovers.
"For us as Palestinians … first of all we hope that he will recover, and second we are looking all the time for a leader in Israel to be in a favor of peace, to be ready to sit with the Palestinians to start a very serious and incredible negotiation. This is what we hope."
Sharon also received get-well-soon messages from the leaders of Russia, France, Germany, Norway, Sweden, and the European Commission.
Turkish Foreign Minister Abdullah Gul praised Sharon as a leader who had taken "courageous steps" in the peace process with the Palestinians.