The "tide of ideas" is turning from Labour to the Conservatives, David Cameron has claimed.

In a speech in his Witney constituency on Thursday, the Tory leader likened the next election to those of 1979 and 1997, years when "the country decided that a new government is the only way forward".

"The tide of ideas has turned, leaving Gordon Brown on the wrong side of history," he said.

He said that Labour's "hyperactive state" and culture of central targets had failed, and would be replaced by a "post-bureaucratic age" in which "we increase wealth by backing free enterprise, markets and competitive tax rates".

Cameron used the speech to hint at a series of upcoming policy announcements on a "supply-side revolution in Britain's schools", a "welfare revolution" and plans for prison reform to cut re-offending.

He said in 1979, when Margaret Thatcher entered Downing Street, it was clear "the age of nationalisation had to end", and said the Conservatives should "never stop taking pride in the magnificent achievements of the Thatcher and Major governments".

But, he acknowledged, in 1997 "people wanted more than a strong economy" and turned to Labour to create "a stronger society; stronger public services".

Labour failed despite increased spending on services, Cameron said, because the party "devoted their energy to the nationalisation of society".

"No social problem... was considered immune to the magic touch of the master bureaucrats," he said.

"It was Brown, not Blair, who created the culture of targets that have blighted our public services.

"Intended to show that public money wasn't being wasted, they instead guaranteed that it was by undermining professional discretion and making public servants accountable to politicians and managers instead of the public."

He said Brown's "one-dimensional anti-poverty strategy" had "left millions dependent on benefits with the labour shortages filled by uncontrolled immigration".

There are now five million adults on out-of-work benefits, he said, and four million of them want to and could work given the right training, incentives and support.

He said the NHS was suffering from "cutbacks and closures" despite a near trebling of its budget, while Britain's schools had "fallen down the international league table" because of Whitehall interference.

"The age of Labour's hyperactive state has failed to deliver the hopes of 1997," he said.

He went on to say Labour had failed to keep pace with "a new world of freedom" where "people expect to make more and more decisions for themselves".

"I sense that we are now on the brink of a new, post-bureaucratic age," he said.

"Opportunity in the post-bureaucratic age is achieved not through complicated and costly government schemes but by giving people control - whether over the money they earn or the services they use."

He said there was an "unmistakable whiff of decay" about the government, describing them as "hapless and hopeless, constantly buffeted around by events".

And referring to the November election considered but eventually ruled out by the prime minister, Cameron said: "Soon there will be a new team in charge. Soon we will see the dawn of a new post-bureaucratic age.

"Change may have been delayed, but I promise you this: Change is on its way."