The Conservative leader is due to say that the government's determination to centralise control is having a detrimental affect on education and healthcare.

The days are long gone when everyone was prepared to put up with poor standards as long as no-one else was receiving anything better

Iain Duncan Smith

In a speech to the Local Government Association's annual conference, which is being staged in Bournemouth, he will say that services are failing to keep in step with rising expectations.

Public services, Mr Duncan Smith will argue, are being run as if it was still 1945, leaving them at odds with the 21st century.

In particular he will criticise centrally-set standards of uniformity.

"Of course, there is a reason why so many believe that uniformity is critical in public services, because, they argue, uniformity is fair," he will say.

"But the days are long gone when everyone was prepared to put up with poor standards as long as no-one else was receiving anything better.

Mrs Addis' case will be highlighted again by the Tory leader

"At the beginning of the new century, equality of mediocrity no longer unites our country, it merely emphasises existing divisions."

He will also say that while the "centralised welfare state" is motivated by compassion, it is failing to produce compassionate results.

"Uniformity has ceased to be a means, it has become an end itself."

He will argue those in the greatest need suffer most from poor services, whether "bad" schools or "unacceptably long" hospital waiting lists.

"There is nothing fair about failing public services that hit the most vulnerable in our society the hardest," he is due to tell delegates.

Political storm

Mr Duncan Smith plans to raise the case of 94-year-old Rose Addis - the mother of one of his constituents, whose treatment in a London hospital hit the headlines earlier this year.

At the time Mr Duncan Smith provoked a political storm by challenging Prime Minister Tony Blair over her treatment, during questions in the House of Commons.

Earlier this week the British Medical Association complained that Mrs Addis' "privacy and dignity were trampled over" in the fallout from the row.

They urged politicians not to pick on individual cases for "point-scoring" purposes.

But Mr Duncan Smith will say: "People would do well to reflect on what kind of unreformed and unaccountable health service it is that embroils senior politicians in the cases of individuals, before criticising MPs for raising the concerns of constituents who feel they have nowhere else to turn."