Tough new powers for the General Medical Council were announced yesterday to ensure doctors struck off the medical register never return to practice, other than in exceptional circumstances.

The GMC will also be given wider powers to suspend a doctor immediately where there is a perceived risk to the public and will be required to warn employers when a doctor is being investigated.

The Government proposals aim to boost public confidence in the GMC following a series of high-profile cases, including that of serial murderer Harold Shipman, which exposed its shortcomings.

The GMC found itself powerless to suspend Dr Shipman after he had been arrested, and was unable to strike him off until after he had been convicted, because of a loophole in the law.

A key area of discontent is that doctors struck off the register have been restored to it and gone back to work. Over the past decade 39 of 153 doctors struck off the register have been restored.

In some cases, those found guilty of sexual offences or of putting patients unnecessarily at risk have been allowed to resume their careers within a few years.

The consultation paper says: "The presumption [should be] that when a doctor is struck off, it is for life, save in the most exceptional circumstances."

Life bans with no appeal have been ruled out because the right of appeal is enshrined in human rights legislation. But, under the new measures doctors will not be able to apply for re-admission to the register for at least five years instead of the present 10 months. The GMC acknowledged yesterday that the tougher conditions could make its disciplinary committee more reluctant to strike doctors off. "We will have to see if there is any impact on sentencing," a spokesman said.

John Denham, the Health Minister, said most doctors were hardworking, honest and trustworthy but the new powers would enable the GMC to take swift and lasting action against the minority whose fitness to practice gave cause for concern. "We recognise that the vital bond of trust that exists between individual doctors and patients has been put under immense strain.

"The Government is not prepared to let a minority of rogue doctors erode that bond. The GMC must genuinely exist to protect patients. It must be truly accountable and it must be guided at all times by the welfare and safety of patients. The GMC will have the responsibility to use these powers effectively."

The GMC, which proposed most of the changes last year, welcomed the move. Sir Donald Irvine, its president, said: "The legislation under which we operate is arcane, out-of-date and cumbersome. These proposals, when they become law later this year, are an important first step in the overhaul of that framework."

The moves are part of the council's attempt to build public confidence in its regulatory function and change people's perception of it from a doctor-protecting organisation to a patient-protecting one. Sir Donald has repeatedly warned that unless the council wins public support, the Government could move to take over regulation of the profession.