An MP has attacked Mayor of London Sadiq Khan’s decision to allow a major housing scheme to go ahead on a disused retail park.

MP for Hendon Matthew Offord accused the mayor of using his powers for “political gain” after Mr Khan gave a developer the green light to build 844 homes in blocks up to 15 storeys high at Pentavia Retail Park in Mill Hill.

Mr Offord has written to Government housing secretary Robert Jenrick calling for a review of the mayor’s decision.

A Barnet Council planning committee refused to grant permission for developer Meadow Residential to build 724 homes at the Pentavia site, which lies between the A1 and the M1, in July last year.

But the mayor used a special ‘call-in’ power to approve an amended version of the scheme featuring a higher number of homes and a greater proportion of affordable housing.

Mr Offord’s letter states: “I believe it is important that decisions, such as planning applications, should not be overturned by higher tiers of government, such as regional mayors or even central government.

“I appreciate the Mayor of London has the power of call-in and, as such, I would not normally take issue with the decision he made, even if I disagreed with it.

“On this occasion, however, I feel strongly that the current mayor is cynically using his call-in power for political ends.

“The mayor was elected on a promise to deliver a certain number of new homes and he has spectacularly failed to do this.

“Now it seems he is prepared to accept any housing project which will allow him to say he has delivered on his pledge at next year’s Greater London Authority elections.”

Under powers agreed by parliament in 2008, the Mayor of London is able to call in planning decisions that are of ‘potential strategic importance’ to London.

These include developments of 150 residential units or more.

City Hall planning officers admitted in a report that the Pentavia plan marked a “departure from Barnet Local Plan policy concerning appropriate locations for tall buildings”.

But they said the fact that the site was “segregated” meant the surrounding area “would not be adversely affected by the proposals”.

Mr Khan approved the development after pointing out that between 2012 and 2017, the number of affordable homes built in Barnet fell well short of the target set out in the Mayor’s London Plan.

A spokesperson for the Mayor of London said: “The sole reason the Mayor called in and approved this scheme was to deliver much-needed affordable homes for Londoners, on a historically under-used site.

“Following Sadiq’s intervention the overall number of homes has been increased by 120 – to 844 homes – and the proportion of affordable homes has been increased to 41 per cent, including social rent and London Living Rent homes for people on lower incomes.”

The Department for Housing, Communities and Local Government was approached for comment.