The government has been accused of bullying NHS officials into using private firms to treat patients.
The government hopes private firms will help to cut waiting times
South West Oxfordshire Primary Care Trust rejected plans last year to pay South African firm Netcare to carry out cataract operations.
It reversed its decision a month later. Its former chairman has told the BBC the trust came under pressure to do so.
The Department of Health said it "makes no apologies" for encouraging the NHS to sign up to the scheme.
The government has signed a deal with Netcare to carry out 41,600 cataract operations over the next five years.
The operations are being done in mobile clinics, which will travel around England.
The board of South West Oxfordshire Primary Care Trust voted against proposals to sign up to the scheme last November only to change its mind at a meeting in December.
The original rejection followed concerns from doctors that any deal would have a serious effect on local NHS services.
Hospital consultants had warned that it would starve local hospitals of cash and affect their ability to carry out more difficult operations and to train doctors.
In December, Sir Nigel Crisp, NHS chief executive, told the BBC that primary care trusts would be given the power to decide for themselves what services they need.
But Professor Martin Avis, the former chairman of South West Oxfordshire PCT, says the trust was ordered to overturn its decision.
"My chief executive was told that the minister required a reversal of the decision on his desk early the following week," he said.
Asked which minister was involved, he replied Health Secretary John Reid.
Professor Avis complained to the chairman of the local strategic health authority. However, it was under pressure from above to ensure PCTs signed up to the scheme.
"We were under tremendous pressure to get a 'yes' vote," Jane Bett, its chairman told File on 4.
She said the health authority was caught in a "tug of war between PCTs and the Department of Health."
Professor Avis was recently asked to re-apply for his job as chairman of the PCT. He decided against doing so.
Jane Hanna, another member of the trust resigned last week. She backed up claims of government interference.
"There is no room for local autonomy," she said.
"I am not really willing to be a rubber stamp for government. The public is sold the message that they are the key to decision making in the NHS today and that is simply not the case."
Sir Nigel Crisp was questioned about the case in an interview with File on 4. However, he walked out of the interview before it had been completed.
Liberal Democrat MP Evan Harris, who represents Oxford West, accused the government of bullying NHS officials into working with private firms.
"I don't think the government should claim its a local decision and then bully behind the scenes," he said.
A spokeswoman for the Department of Health said: "The Department of Health makes no apologies for encouraging the NHS to take up innovative and successful schemes.
"Thousands of patients have had their cataract operations more quickly, free at the point of need, as a result of this deal".
She added: "It is for the local NHS to decide how best to meet the health needs of its local people, and we refute any claims of coercion."