Former German foreign minister Hans-Dietrich Genscher, who played a central role in ending the Cold War, has died at age 89, his office announced on Friday.
As Germany's longest-serving foreign minister, Genscher was a major force in driving the events surrounding the collapse of communist rule across Central Europe and the breaching of the Berlin Wall in the 1980s.
German Chancellor Angela Merkel, who grew up in communist East Germany, acknowledged the decisive role Genscher played "as an unmistakeable voice that gave me as well as millions of people in East Germany and Eastern Europe the hope for change."
"I bow in respect for the lifetime achievements of this great liberal patriot and European," said Merkel.
In September 1989, Genscher appeared on the balcony of the then West German Embassy in Prague to tell the 4,500 East Germans who had gathered in the building's grounds hoping to escape communism that a deal had been reached allowing them to travel to the west.
His announcement represented one of the most emotional moments in German history and helped to pave the way for the fall of the Berlin Wall and ultimately to Germany's historic unification in 1990.
"European unity is the answer to the mistakes of the Germans and of European history," Genscher said in a speech in the German parliament.
"It is the answer to a terrible world war," he told lawmakers before stepping down from parliament in 1998.
"Genscher made history and shaped our country," Christian Lindner, the leader of Genscher's pro-business Free Democrats (FDP), wrote in a Tweet.
"We owe him a lot," said Lindner who saw Genscher as a political mentor. "Our grief cannot be greater."
Lindner's comments were echoed by Germany's current Foreign Minister Frank-Walter Steinmeier who described Genscher as "a great German and a great European."
Tributes flowed in from around the world with French Foreign Minister Jean-Marc Ayrault also honouring Genscher as "a convinced European."
"It is also a result of his work, that today we have a European Union of 28 members," said European Commission chief Jean-Claude Juncker.
The EU has dramatically expanded its membership over the last decade or more, taking in a raft of new members including former communist Central and Eastern European states.
Born in the eastern German city of Halle, Genscher served as foreign minister for almost two decades until 1992.
He held the post of Germany's chief diplomat in coalition governments first headed by Social Democrat chancellor Helmut Schmidt and then by conservative Christian Democrat chancellor Helmut Kohl.
In the early 1990s he joined Kohl in talks with former Soviet leader Mikhail Gorbachev that helped to pave the way for German unification and ending the nation's post-Second World War divide.
"People say that you cannot have any friends in politics," said Gorbachev in his tribute to the former foreign minister.
"That's not true," said Gorbachev said. "Hans-Dietrich Genscher was my real friend in recent years. I have lost a friend."
With his trademark yellow pullover, Genscher became one of Germany's most popular politicians before bowing out of office in 1992. He also previously held the post of interior minister.
He died late on Thursday of cardiovascular failure, according to his office.