A petition to return the Rosetta Stone to Egypt has gained 100,000 supporters, the archaeologist behind the campaign has said.
But Dr Zahi Hawass said he wants a million signatures before he sends the petition to the British Museum.
Dr Hawass, a former antiquities minister in Egypt who regards the stone as stolen, is also lobbying museums in Berlin and Paris to return other Egyptian treasures.
He told The National that the British Museum could live without the stone given its large collection from Ancient Egypt.
“The British Museum can say what they want, but it is important for the Rosetta Stone to return,” he said.
“They have thousands of Egyptian objects on display and in storage, and their collection won't be greatly affected.”
The stone is currently part of an exhibition marking 200 years since its ancient languages were decoded.
Inscribed in Egypt in about 200 BC, it was discovered by French troops in 1799 but acquired by Britain under a treaty in 1802.
Its Ancient Greek text allowed scholars to translate the two ancient Egyptian scripts alongside it, written in formal hieroglyphics and an everyday script called demotic.
Since being taken to London, the only time it is known to have left the British Museum was in 1917, during the First World War, when it was moved to a railway tunnel to keep it safe.
The campaign to return it to Egypt comes amid a changing mood in western countries about the proper home of colonial-era loot.
Dr Hawass’s petition says that “with the whole world talking about the decolonisation of western museums, it seems absurd” for the British Museum to retain the stone.
It also calls on the Louvre in Paris to return the Dendera zodiac, part of a ceiling that was once in an Egyptian temple.
“I am waiting for one million signatures and this is when I will send the letter officially and will use the press to pressure the British Museum and the Louvre to return these pieces,” Dr Hawass said.
“Their rightful place should be the Grand Egyptian Museum which is opening very soon to the public.”
The British Museum’s position is that it has never received a formal request to repatriate the stone.
“At the British Museum, visitors can see the Rosetta Stone alongside other pharaonic temple monuments, but also within the broader context of other ancient cultures,” it said in a statement to The National in August.
A third artefact that Dr Hawass regards as stolen, a bust of Queen Nefertiti, is held by a museum in Berlin.
He started gathering evidence of theft after the London, Paris and Berlin museums rejected his bids to take the items on loan in 2010.
His campaign stalled amid the 2011 uprising in Egypt, which brought an end to his political career.
But he remains a prominent figure in Egyptology and believes people in Europe are awakening to his cause.
“The Rosetta Stone is the icon of our identity as Egyptians and this is why I wrote this petition,” he said, “and also with the Zodiac because it has been cut from the temple ceiling during imperial times".
“How come we have the replica and the original is in the Louvre?"