Michael Gove is to relax planning rules in England in an effort to create more homes in “the hearts of our cities.”

The levelling up secretary says he wants to make it easier to convert empty retail premises and betting shops into flats and houses. But critics say such conversions are often poor quality. It comes as Rishi Sunak insists his party will meet its commitment to building a million homes before the next election, expected in 2024.

A report by the Commons housing committee earlier this month found that while ministers are on track to deliver its 1m homes target, they are not expected to meet their other commitment to deliver 300,000 new homes every year by the mid-2020s.

Hitting that figure became harder after the government was forced to water down its housing targets for local councils following a fierce backlash from its own MPs, many of them in rural constituencies.

The prime minister said his government would not be “concreting over the countryside”. However, the Office for National Statistics reported in October last year that residential property covers just 1.3% of all the land in the UK, plus 4.9% allocated to residential gardens. This means that only 6.2% of total UK land is allocated to homes and private gardens.

Sunak added: “Our plan is to build the right homes where there is the most need and where there is local support, in the heart of Britain’s great cities.”

Lisa Nandy, Labour’s shadow housing secretary, said: “It takes some serious brass neck for the Tories to make yet more promises when the housing crisis has gone from bad to worse on their watch.”