A council has agreed to loan developers of one of the world's largest freshwater aquariums more public money to help get the scheme off the ground.
The project would be four times larger than the Eden Project
The National Institute for Research into Aquatic Habitats (Nirah) wants to build the development in an old quarry at Stewartby, near Bedford.
Bedfordshire County Council agreed on Tuesday to loan another £300,000. Nirah has already received £3m in loans.
The loan is subject to conditions which Nirah will review on Wednesday.
A Nirah spokeswoman said a number of conditions on the loan, including changes to terms and conditions, are likely to make it impossible for Nirah to accept.
Nirah has already received £3m in loans to develop a business plan and seek planning permission.
The research complex and aquarium, would be four times larger than the Eden Project, in Cornwall.
The 40-hectare complex in an old brickworks is the brainchild of an international team of biologists and conservationists.
The chairman of Nirah will be in Bedford on Thursday to announce the board's response to the council's "offer".