Plans to “root out” problems in the care of older people will see hundreds of hospitals and care homes subject to higher numbers of unannounced checks.

Health Secretary Andrew Lansley will announce the drive in the wake of a report by the Care Quality Commission that raised serious concerns about the treatment of elderly patients.

The latest wave of inspections will cover 50 hospitals, 150 centres housing people with learning disabilities, and 500 elderly care homes.

The CQC will focus on “core dignity issues” such as privacy and standards of nutrition.

In a speech, Mr Lansley will insist NHS organisations “owe it to their local communities” to improve performance.

“Too often, we deny the experience of patients and their family members who have been at the sharp end of appalling treatment,” he is to say.

“This is why I asked the CQC to do more unannounced inspections in our hospitals and in care homes, and to take tough action if what they find is unacceptable.

“I want to modernise the NHS because I believe it can and should offer excellent care to every patient, no matter where they live, how old they are or how sick they are; combining access for all with excellence for all.

“I want the NHS to lead the world in everything it does, not just some of what it does.

“Unless we face up to its challenges; unless we take action when it lets patients down, it will never be able to do this.”

Mr Lansley will accuse a succession of Labour health secretaries, including Andy Burnham, of having failed to get a grip on the situation.

“Where there is great care, we will celebrate it,” he is to say. “But wherever there are pockets of poor performance, we will root it out.”

The pledge comes as Liberal Democrat peers signalled the end of their rebellion against the government’s controversial NHS reforms.

The government on Tuesday accepted an amendment to the legislation clarifying that the secretary of state will remain directly responsible for health service provision across England.

In a letter to the Guardian, Lib Dem peers including Baroness Shirley Williams wrote: “The time for declaratory statements is past.

“Patients who care passionately about the NHS and staff who want to give the best possible service, need certainty about the future of the health service.

“Any politician who plays party political games with the NHS would be open to justified public criticism. So it is now imperative that members of the House of Lords get on with their job of subjecting this bill to detailed, rigorous scrutiny.”

The letter made clear how important they regard the climbdown by Mr Lansley over his stated role. “In order to safeguard the NHS, free at the point of need and accessible to all, Liberal Democrat peers are putting forward amendments which require the secretary of state to remain responsible for health services being provided across England,” it insisted.

However, shadow health secretary Mr Burnham will use an Opposition Day debate to up his rhetoric on the reforms, dubbing them “Cameron’s NHS betrayal”.