Judges instead of ministers are to be given the exclusive right to allow cases involving national security to be heard behind closed doors, in a major government concession to critics of its “secret courts” plans.

The proposal to allow members of the security services to give evidence in secret in civil courts has been condemned by opponents as undermining a key tenet of English law which guarantees that proceedings take place in public.

Hundreds of peers joined the attack last month, demanding significant changes to the Justice and Security Bill as they defeated the Government three times over the measure. The Coalition is preparing to accept all three amendments when the Bill reaches the Commons in an effort to avert a rebellion by Liberal Democrat and Conservative critics. Ken Clarke, the minister without portfolio, who is overseeing the Bill, is expected to make the announcement next month.

The effect of the U-turn will be to give the judiciary the final decision over whether to order a secret session. The Bill originally proposed giving ministers the power to instruct judges to hear evidence in camera and specify which material could be concealed from the public, the media and even claimants.

Judges will also be required to balance any harm from disclosing security information against the open administration of justice when they consider whether to move to so-called “closed material proceedings”. In a third concession, claimants – not just ministers – will be allowed to apply for their cases to be heard privately if they thought secret material could help.

A senior Government source said: “We will be accepting the amendments in full. Everyone involved can live with them.”