World leaders have been contacting Polish Prime Minister Donald Tusk to express their condolences at the terrible human and political tragedy that has befallen Poland. A hundred of the country's top military and political leaders died in the crash of the presidential plane in western Russia en route to an event marking the 70th anniversary of the massacre of thousands of Polish officers by Soviet secret police at the beginning of World War II.President Barack Obama called Kaczynski a distinguished statesman who was widely admired in the United States as a leader dedicated to advancing freedom and human dignity."Our thoughts and prayers are with the Kaczynski family, the loved ones of those killed in this tragic plane crash, and the Polish nation," Obama said in a statement.He described Poland's civilian and military leaders who died with Kaczynski as having helped shape that country's "inspiring democratic transformation.""On this difficult day the people of Russia stand with the Polish people," Russian President Dmitry Medvedev told Polish Prime Minister Donald Tusk.German Chancellor Angela Merkel recalled her meetings with Kaczynski and said that "we always found a result in the end.""I knew that his whole life had been dedicated to the fight for the freedom of Poland and the freedom of Europe," she said. "We will miss Lech Kaczynski in Germany too," she said. "Germany is mourning today with the whole Polish people.""Ithink the whole world will be saddened and in sorrow as a result of thetragic death in a plane crash of President Kaczynski and his wife Mariaand the party that were with them," British Prime Minister Gordon Brownsaid. "We know the difficulties that Poland has gone through, thesacrifices that he himself made as part of the Solidarity movement. Weknow the contribution he made to the independence and the freedom ofPoland."French President Nicolas Sarkozy in a statement paid tribute toKaczynski. "Lech Kaczynski devoted his life to his country. A tirelessdefender of the ideas in which he believed, he always battled withconviction for the values that founded his entry into politics:democracy, liberty and the fight against totalitarianism," Sarkozy said.Italian Premier Silvio Berlusconi said "It is a grave loss that hasstricken a friendly country and in which I am sharing in with my heart."U.N. Secretary-General Ban Ki-moon said Kaczynski had "served hiscountry and people with distinction and conviction, and was deservedlyrespected internationally. That he died en route to an event marking anew level of reconciliation between Poland and Russia is particularlypoignant."Pope Benedict XVI said in a condolence message that he learned of thedeaths with "deep pain" and that he wanted to assure the Polish peopleof his "spiritual closeness" in this moment."Ukraine has learned about the plane crash ... with great sorrow andinexpressible pain," Ukraine's President Viktor Yanukovych said in astatement. "We share the deep pain of a loss that hit the friendlyPolish people and mourn together with the families of the dead."Former President George W. Bush said in a statement that he's deeplysaddened by the news of Kaczynski's death. He and former First LadyLaura Bush have fond memories of visits with Kaczynski and his wife,Bush said, and want to express their condolences to the families of allthe people killed in the crash.