A diplomatic row between Germany and Egypt over rights to the 3,400-year-old bust of the fabled Queen Nefertiti reopened yesterday when Berlin flatly refused to accept an official request from Cairo to return the priceless artefact to the banks of the Nile.

The world-renowned bust has been on public display in Berlin since 1923 following its discovery by the German archaeologist Ludwig Borchardt at Amarna in 1912. It rates as one of the capital's top tourist attractions and is seen by some 500,000 visitors a year.

Egypt, which argues that Germany obtained the bust illegally and by deceit, has been lobbying for Nefertiti's return for more than half a century. But on Monday, Zahi Hawass, the head of Egypt's Supreme Council of Antiquities, declared that an "official request" had been sent to Berlin demanding the bust be handed back.

"We ask that this unique treasure be returned to the possession of its rightful owners, the Egyptian people," the statement said.

Mr Hawass said the demand had received the full backing of the Egyptian Prime Minister and Culture Minister and was submitted to both the German government and the Prussian Cultural Heritage Foundation, which runs Berlin's Neues Museum, where Nefertiti is on permanent display.