Sadiq Khan’s London development plan is working to “frustrate rather than facilitate the delivery of new homes”, according to a Government-commissioned report.

The independent review, ordered by Housing Secretary Michael Gove last December and published on Tuesday, recommended making it easier to get permission to build on brownfield sites in the capital.

But it was rejected by the London Mayor, who branded it a “stunt” and accused Rishi Sunak of “undermining devolution”.

The 46-page report, following a review led by barrister Christopher Katkowski, considered whether changes might be required to the 542-page London Plan to boost housing provision on brownfield land.

It found that there is “persuasive evidence that the combined effect of the multiplicity of policies in the London Plan work to frustrate rather than facilitate the delivery of new homes on brownfield sites, not least in terms of creating very real challenges to viability”.

“There is just so much to navigate and negotiate that it should come as no surprise that wending one’s way through the application process is expensive and time-consuming.

“Without a step change, it is highly unlikely that the housing targets of the London Plan will be met within its 10-year period and, as a consequence, the current housing crisis will continue, if not worsen.”

The review also noted the London plan was not the “sole source” of the problem, also pointing to wider economic conditions, fire safety and pressures on planning resources as among a host of other factors.

In a letter to the London mayor along the report, Mr Gove also said he was “seeking views on whether changes are required to the threshold at which a residential planning application is referrable to you as the Mayor of London, which is currently set at 150 homes or more”.

Published early on Tuesday, Mr Gove wrote: “The Government will not hesitate to go further, making sure that our capital city has the housing it needs.

“Alongside consulting on these changes, I want to inform you that I am also announcing £50 million of new investment in London to unlock new homes through estate regeneration.”

Mr Khan, who faces re-election in May, hit back with a defence about of his housebuilding record.

A spokeswoman for the London mayor said: “The facts are clear – London under Sadiq Khan is outbuilding the rest of the country. Housing completions in the capital have hit the highest level since the 1930s, according to the Government’s own data.

“London is also delivering twice the level of council homebuilding as the rest of the country combined, showing up ministers’ dismal failure nationally.”

Accusing ministers of previously ignoring calls for greater investment in brownfield development, she said Mr Khan would not “take lectures from a government that has scrapped housing targets nationally and sent people’s rents and mortgages soaring”.