A 34-year-old Sarkozy appears to wield a small pickaxe in his Facebook photo
French President Nicolas Sarkozy has posted on Facebook a picture of himself at the Berlin Wall, saying he had chipped away at it with a pickaxe.
Mr Sarkozy joined world leaders in Berlin to mark the 20th anniversary of the fall of the Wall on 9 November.
The image shows Mr Sarkozy, then a 34-year-old French MP, standing before a graffiti-covered section of the wall.
A caption dates the photo "9 November 1989", but the man who took it said it was definitely from the following day.
"I was the photographer and that picture was definitely taken on 10 November 1989," Paul Clave - who was at the time a representative for French interests in Berlin - told the BBC.
In the caption, the French president says he arrived in West Berlin with a group of French politicians on the morning of 9 November, crossed Checkpoint Charlie to the East, and headed for the Brandenburg gates.
Paul Clave said he definitely took the photo on 10 November
"An enthusiastic crowd had gathered to welcome the looming opening of the Wall," he writes under the picture, posted on Sunday.
"We then headed for Checkpoint Charlie to see the eastern side of the city and finally confront this wall and I was able to take a pickaxe to it," he writes.
"The night continued in a climate of general enthusiasm: the German people were reunited, heralding the end of the Cold War and the beginning of a period of great freedom in Europe," he says in comments translated from French.
"It is this freedom that we are still defending in Europe and that we are celebrating 20 years on," writes Mr Sarkozy.
However, French commentators point to a possible mix-up of the dates.
They say news of the collapse did not come until late in the day on 9 November, and West Berliners did not begin attacking the Wall until the following day.