Schools in England are to be subject to more frequent, shorter inspections, Ofsted has revealed with the launch of a new consultation document titled Better inspections for all.

Writing in paper's foreword, Ofsted's chief inspector Sir Michael Wilshaw said that unannounced inspections will not be standardised, much to the delight of teachers across the country.

The controversial measures, which were first proposed by Sir Michael in 2012, had been heavily criticised by the teaching profession.

In his foreword, he continued by saying that the oversight between inspections is "not as effective as it should be".

Presently, for example, it can be half a decade or more between inspections for a good school or college, he explained.

This, he continued is far too long for all stakeholders, including students, parents and even employers.

Moreover, this makes it harder to spot declines in standards before they become serious problems and, on the flip side, it means schools that are making a real difference miss out on the credit they deserve.

"The time has come, therefore, to introduce more frequent but shorter inspections for good schools and further education and skills providers," he said.

"These inspections will differ from previous practice and will focus on ensuring that good standards have been maintained.

"In particular, inspectors will be looking to see that headteachers and leadership teams have identified key areas of concern and have the capability to address them."

In related news, the Guardian has received an internal Whitehall memo that suggests former education secretary Michael Gove was considering replacing Sir Michael as chief inspector.

The Department for Education document showed that Mr Gove and his colleagues were becoming increasingly concerned about the direction of Ofsted under Sir Michael.

Written by Dominic Cummings, formerly Mr Gove's special advisor, the memo shows a lot of unease about the department's future.

"Despite constant pressure from us and constant assurances, there is no evidence that [Wilshaw] is substantially changing the organisation," Mr Cummings is alleged to have wrote.

"And considerable evidence from a constant flow of blogs and emails that problems are either the same or getting worse."