Andy Burnham is backing Shabana Mahmood’s stringent efforts to crack down on immigration, his allies say – in an effort to win votes from Reform UK supporters.The mayor of Greater Manchester reportedly wants to “reframe” the home secretary’s changes but backs her attempts to limit legal and illegal migration, according to sources in his team.Next month’s by-election in Makerfield is expected to be a close contest between Mr Burnham and Reform UK, which made recent council gains in local elections.Reform has previously dubbed him “open-borders Andy” but those close to his campaign have told The Guardian he will not want to dilute the government’s curbs on migration.Home Office reforms to migration rules under Ms Mahmood include ending the right to permanent refugee status and new settlement rules for people who have come to the UK since 2021.Under the plans, the default qualifying period for Indefinite Leave to Remain (ILR) will be increased from five years to 10, and migrants could be eligible for benefits and social housing only once they become British citizens.Those granted asylum whose country is later deemed to be safe will also be asked to leave.Ms Mahmood has introduced tougher rules for immigrants (AFP/Getty)And people in the country illegally could have to wait up to 30 years for long-term residency in the UK.But the government could face pressure from Labour backbenchers to abandon its reforms after new figures are expected to show that net migration has declined to its lowest level since the pandemic.“For Andy, migration is a moral issue as much as anything, showing people who’ve lost faith in politics that we do have control and we can do good,” one source said.“We need to tell a positive story about the contribution of migration to our country, but we cannot do that unless people trust that the people they vote for have control over our borders.”Labour MP Andy McDonald previously said: “There is something innately un-British in changing the qualifying period for ILR retrospectively, which will cause massive upheaval for workers who have already come and settled here at our request.”Migration expert Dr Ben Brindle, of the Migration Observatory at the University of Oxford, said the latest figures from the Office for National Statistics could show that net migration had fallen below 200,000 for the first since March 2021. But he said the fall was expected to be only temporary.If he returns to Westminster, Mr Burnham is expected to challenge Sir Keir Starmer as Labour leader and prime minister, having gathered a head of support as the prime minister has drawn increasing criticism.A source close to his campaign said: “Immigration is the second most important issue there. He must show decisive leadership on this and reframe but back the reforms to restore control over our borders and create a firm but fair migration system.”But key figures from Labour’s Blue Labour movement have publicly backed the home secretary as the party's next leader – a blow to Mr Burnham’s leadership ambitions.The Independent has approached a spokesperson for Mr Burnham. A spokesperson for Ms Mahmood declined to comment to The Guardian.