German officials have ruled out returning an ancient bust of Queen Nefertiti to Egypt - saying it is too fragile to be transported, dpa reported.
And they have insisted that the bust was acquired legally by the Prussian state nearly a century ago.
Egypt first requested the return of the antiquity in 1930, but successive German governments have refused.
Head of antiquities Zahi Hawass says the bust was smuggled out of Egypt by a German archaeologist in 1913.
Mr Hawass claims the archaeologist, Ludwig Borchardt, disguised its true value by covering it in a coating of clay.
The 3,300-year-old bust is the star attraction of the Egyptian collection at the Neues Museum in Berlin.
The collection's director, Friederike Seyfried, said: "The position of the German side is clear and unambiguous - the acquisition of the bust by the Prussian state was legal."
Queen Nefertiti is renowned as one of ancient history's great beauties.
She was the wife of Pharaoh Akhenaton - who initiated a new religion which involved worshipping the sun.
Egypt has been aggressively campaigning for the return of ancient artefacts, and last week secured the repatriation of fragments of a 3,200-year-old tomb from the Louvre.
Earlier this month Mr Hawass said he would drop a similar demand for the permanent return of the Rosetta Stone if the British Museum agreed to loan it.
The stone is a basalt slab dating back to 196 BC which was key to the modern deciphering of hieroglyphics.