A 61-page international petition has urged York's councillors to back a last-ditch fight to stop "Coppergate II".
The Castle Area Campaign group sent the document to every City of York Council member asking them to oppose plans for the proposed £60 million shopping development in the shadow of Clifford's Tower.
A decision on whether the scheme can go ahead is expected from the Government before the end of this month.
The petition includes names of people living in Britain, the USA, Canada, New Zealand, Singapore and Mexico. And it has been sent with a message from campaigners.
It says: "There is still time for City of York Council to rein in its rogue elements. The redevelopment can be constrained to the Piccadilly side of the River Foss and our heritage and environment can be safeguarded for everyone's enjoyment. What will you do to stop Coppergate? How will history judge you?"
Messages, gathered on an internet site set up by a campaign supporter in Florida, include those from ex-pats living abroad, as well as visitors to York.
Florida-based Andy Royston said: "Clifford's Tower might not sell T-shirts or attract the multitude of coach parties, but its importance in Yorkshire's cultural history cannot be understated. It must not be allowed to become the backyard of some ill-planned shopping mall."
New Zealander Patricia Faulkner said: "The tourists can see all the shops they need at home. They come to York for the history."
Anis Martin Kashani, who lives in Texas, asked councillors: "How many beautiful sites in your country have been lost forever by the construction of modern buildings adjacent to historical ones? How will those of us born in a country hardly a few centuries old ever see such sites if they are altered by modern structures?"
The Coppergate Riverside development, which was approved by councillors in 2000, was called in by Deputy Prime Minister John Prescott and was the subject of a lengthy public inquiry. The result of that is expected this month.
Stuart Wilson, spokesman for the Castle Area Campaign, said: "We're so impressed with people's support nationally and internationally.
"We believe that there is still time for the council to stop this madness."
Updated: 08:55 Thursday, July 03, 2003
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