Sir Alistair Morton said Connex had tried hard but did not succeed

Connex lost the franchise to run services in Kent and Sussex after the Strategic Rail Authority (SRA) decided its financial management was too poor.

The firm, whose contract had been due to run until 2006, will operate services for the next six months, after which an interim company will take over until a new private operator is found.

But Sir Alistair Morton, former chairman of the SRA, told the BBC on Tuesday it could be difficult to find an operator willing to take on the task.

It is a poisoned chalice and I imagine for enough money somebody will take it on Sir Alistair Morton

"It is a poisoned chalice and I imagine for enough money somebody will take it on and it will be possible to improve it by a different management approach.

"But I know Connex tried hard - they just didn't succeed."

He said the company's management was not solely to blame for its failure.

"There are quite a lot of external influences beyond the control of the operator in south-east England that make it extremely difficult to run a really good, punctual service," he said.

Under-investment

Sir Alistair said Connex had inherited an infrastructure weakened by years of under-investment under nationalisation and privatisation.

"The government now isn't planning to put much capital in so the operator is struggling with more automated train stock and more trains that make it very hard," he said.

"I just think the bill will go up and the government's and the SRA's task will be to find someone capable of spending it to the best advantage in difficult circumstances.

"Until Network Rail is spending on improving the infrastructure, it's going to be very difficult for anyone to run a really good service."

Current SRA chairman Richard Bowker told the BBC last week there had been a "serious loss of confidence" in the ability of the French-owned company to run the franchise.

Connex remains Europe's biggest private rail operator, however, with an annual turnover of �2.3 bn (3.4bn euros).