Thousands of people gathered for the celebration on October 3. Capitalist West and communist East Germany merged on October 3, 1990, nearly a year after the fall of the Berlin Wall which divided them.

German President Christian Wulff told the assembled dignitaries: “They remembered the momentous day that a people rarely experience. I bow before everyone who fought for freedom... your courage moved the world".

On the eve of the anniversary, US President Barack Obama passed on his congratulations and said Germany was "one of the US closest allies and greatest friends".

Mrs Merkel, who was brought up in the East, praised former East Germans for fighting for their freedom.

"At the same time, there was a huge wave of solidarity from the people in West Germany”, she said. “It is thanks to these joint efforts that we have been able to rebuild so quickly and make Germany a country that is respected in the world."

Since the two countries became one, more than 1.5 million people have migrated west.October 3 was also the day Germany made the last payment on debt stemming from reparations imposed after World War I.