The city has a £300,000 guarantee against a Lloyds Bank loan to European News Service, which is chaired by Mr Plowright, who rose to fame as the driving force behind successes such as Brideshead Revisited and World in Action.
On Friday, Michael Short, chief executive of ENS, denied a local newspaper report that Lloyds had called in the guarantee. "ENS is still operating with an understanding banker," he said.
"We are not writing cheques on our account, but reports that the account has been closed are untrue."
"We are just one of 25 companies in this area held up by delayed EU funding," he added. "We have enemies who leaked our confidential request for council help to pay the rent on our offices. But thanks to an understanding landlord, we have not lost our offices."
Mr Plowright told Liverpool's chief executive, Peter Bounds, last October that the project, run by two of his former Granada TV staffers, was in difficulties.
Liverpool had guaranteed the loan after a 1993 seminar at which Mr Plowright was introduced to councillors. "Getting Plowright to Liverpool was like getting Busby to Anfield," said Councillor Harry Rimmer. At the time, the council's head of economic initiatives reported that "the risk attached to this guarantee will not be more than 20 per cent".
ENS planned to set up the Satellite Collection Centre in Liverpool, which would employ 46 people and control news gathering bureaux in Brussels and Prague.
Mr Short, 46, who set up Granada TV's news centre in Albert Dock, Liverpool - and organised the "Waddington Experiment", in which Granada filmed a Lancashire village getting its own cable TV service - worked on the launch with Brian Thomas, 43, the director of operations who had previously worked for NBC and Granada.
Both men were paid £4,000 a month, working in waterfront offices provided under a rent grant by the Merseyside Development Corporation . They stopped taking their salaries last November.
Their "co-operative of European broadcasters" was said to be chasing a £450,000 DTI selective grant, a £2m European Union soft loan, an equity stake of £1.5m from the Dutch electronics group Philips, a £500,000 equity stake from Conus, the pioneering US TV news exchange, and support in Prague through the Soros Foundation.