A charity which runs two zoos in Norfolk and Suffolk has warned it could collapse if they are not allowed to reopen soon.
With much of the leisure sector starting to return following the coronavirus lockdown, the government are still advising zoos to remain closed.
The Managing Director of the Zoological Society of East Anglia (ZSEA), which operates Banham Zoo in Norfolk and Africa Alive in Suffolk, said she is "incredibly frustrated and disappointed" by the stance, and warned they only have a month to survive.
Claudia Roberts added: "Africa Alive and Banham Zoo are in spacious open parkland.
"They’re in a controlled environment and we’ve invested to get everything safe and ready for visitors to return. If we can’t re-open in July, it could finish us.
"Garden centres could put plants in the bin, but what would we and all other zoos across the country be expected to do with our animals if we had to close?”
The ZSEA negotiated a £900,000 loan at the start of the outbreak, but the repayment schedule was based on the assumption they would restart in June.
A statement from the charity said: "If reopening is delayed until August [we] will not survive.
"It desperately needs income from admissions or additional funds and is now trying to renegotiate the loan and apply for further funds."
Last week the Society announced plans to cut up to a third of their workforce, adding that it had lost £1.5 million since the zoos closed.
Watch Becky Jago's interview with Claudia Roberts
The charity's call for an expedient reopening has received political support from Peter Aldous and Liz Truss, the MPs for Africa Alive and Banham respectively.
Charity officials will also meet members of DEFRA today to highlight the issue.
Andrew Selous, the Conservative MP for South West Bedordshire, has also added his voice to calls to reopen zoos.