Plans to build a £92 million stadium for England's World Cup bid were in doubt on Friday after campaigners won a significant victory in their bid to protect the site from development.
People living near the 42-acre stadium site in Bristol are celebrating after an independent inspector said the land should be given town green status.
Bristol City, who wanted to build the 30,000-seat stadium, said they were disappointed but remain determined to press ahead with the scheme.
The deputy leader of Bristol City Council, Simon Cook, voiced shock at a decision which he said could spell the end of a project which would have created thousands of jobs and seen millions of pounds invested in the area.
The decision to protect the land in the Ashton Vale area of the city came after a public inquiry which took evidence from people who wanted the area protected.
The report will now go to the council's public rights of way and greens committee and, if approved, would rule out development on the site for good.
Mr Cook said: "I am shocked and disappointed at the independent inspector's conclusion. Although I respect the fact that she has found that there is a case for awarding a village green, designating the whole 42 acres in question seems utterly unreasonable.
"The new stadium, a possible arena, redevelopment of Ashton Gate and Bristol's World Cup Host City status are at serious risk. This amounts to around £150million worth of investment, promising at least 1,000 extra full and part-time jobs and thousands of construction jobs.
"It also means we risk losing the economic impact of hosting the World Cup, amounting to possibly £150million. The law behind this application is a complete nonsense, but I am utterly determined to find a way through it.''
Bristol City chief executive Colin Sexstone said: "We are naturally disappointed to hear about the report. We always knew that prizes on the scale of a new regional stadium and a World Cup were never going to fall into our lap - the most ambitious and visionary projects never do. But we remain utterly determined to get there.''