Rishi Sunak is embroiled in a growing rebellion over his ban on new onshore windfarms as the former Conservative chairman Jake Berry became the latest senior MP to announce he would join an effort to overturn the policy. The former cabinet minister said he would support the former levelling up secretary Simon Clarke, who has tabled an amendment to legislation going through parliament demanding the current moratorium on new developments be lifted. He joins the former prime ministers Boris Johnson and Liz Truss, and the Cop26 president, Alok Sharma, in urging a climbdown from the prime minister. The levelling up secretary, Michael Gove, has spoken in the past about the need for more onshore wind power, raising the prospect of cabinet splits on the issue. More than 30 Tories are now believed to back the Clarke amendment to the levelling up and regeneration bill, which would allow windfarms in rural areas where there is community consent. Labour has confirmed it is backing the amendment, increasing the likelihood of Sunak suffering a damaging defeat. Gove and Tory party whips are understood to have spent the weekend talking to rebels, while Downing Street insiders suggested it was “very unlikely” that the prime minister would accept Clarke’s amendment amid concerns that he would look weak if he was forced to back down. Berry, who was sacked as party chair by Sunak, said the new prime minister had six months to get a “grip’” as he was hit by a double Tory revolt over planning – with MPs threatening to vote against housebuilding targets as well. He told the BBC’s Sunday with Laura Kuenssberg programme: “Boris Johnson famously used to call wind turbines the white satanic mills of the north of England when they were building them all over my constituency. “He’s changed his mind on them, I to a large extent have changed my mind, and I’m going to be supporting Simon Clarke and his amendment because I think if you want to know why we should have more renewables, just look at your gas or electricity bill.” Since 2014, planning rules have in effect barred new onshore windfarms in England under a tightening of restrictions imposed by David Cameron’s government after pressure from Tory activists. The push for greater energy independence since Russia’s invasion of Ukraine has prompted calls for this to end. Truss had promised to change the rules but was ousted before she was able to do so. Ed Miliband, the shadow climate secretary, said: “Onshore wind is the cheapest, cleanest energy we have. The Tories’ ban has kept bills high and damaged our energy security. Rishi Sunak’s weakness means he’s having to be dragged to scrap it by his backbenches. He should swallow his pride and U-turn now. “Labour will support the Simon Clarke amendment, but even that swaps the ban for what is still a highly restrictive planning regime on onshore wind – risking blocking developments and keeping bills high. Under this government, we’re forced to move only at the pace of the slowest Tory backbencher.” Johnson did not seek to overturn the effective moratorium on new onshore wind projects during his time as prime minister but has since changed his mind. Sharma said he supported letting “local communities decide”, backing residents being given reduced energy bills in exchange for their support of new developments. The row over onshore windfarms is the second major challenge to the bill. Last week, No 10 pulled a scheduled vote after a rebellion over planning policy. However, despite fears it had been kicked into the long grass, government aides said MPs would get a chance to vote on the legislation before Christmas.