Nicola Sturgeon has announced that a payment for children in low income families in Scotland will double to £20 a week next year, arguing that combating poverty was central to her vision for independence. The first minister said the increase in the Scottish child payment would first take affect for families in poverty with children under six from next April, before being expanded to those with children under 16 by the end of 2023. In a prerecorded speech to a Scottish National party conference on Monday, she said it would eventually support 400,000 children and was “the most ambitious antipoverty measure anywhere in the UK”. She told delegates this policy, which has been championed by anti-poverty campaigners and had been previously resisted by Sturgeon’s ministers, was further evidence of the case for independence. The Scottish government said the uplift, which has become affordable after a £4.6bn boost to Holyrood’s funding from the Treasury in last month’s UK budget, would cost £360m a year. Sturgeon said the decision by the UK government to scrap its temporary £20 uplift to universal credit, during the Covid pandemic, was “cruel and shocking”. Poverty “deprives too many children of the chance to make the most of their education and enjoy life to the full, and it robs of our country far too much potential”, she said. “Eradicating child poverty is essential if we are to build the strongest foundation for Scotland’s future.” Cutting universal credit illustrated Scotland’s divergence from the UK government’s approach, she said. Boris Johnson was also threatening a fresh trade crisis with the EU and had deliberately underminedScotland and Wales by expanding Whitehall’s powers over devolved policies. “This crystallises the choice Scotland faces,” Sturgeon said. “If we don’t choose to move our parliament forward and make it stronger with independence – the Tories will drag it backwards and make it weaker.” But Sturgeon chose her words carefully on the timing of a second independence referendum, and offered no new information on plans to stage one. She confirmed to delegates her government planned to “initiate the process necessary to enable a referendum before the end of 2023”, but said resuming the campaign for independence in 2022 was “Covid-permitting”. Recent opinion polls show support for independence has fallen by around 10 points since peaking at 58% last year, and lags behind support for remaining in the UK. Opposition parties believe voter dissatisfaction with the SNP’s domestic record is harming support for independence. A YouGov poll for the Times last week put the no vote at 53% and yes at 47%; the same survey found Sturgeon’s approval rating had slumped from a peak of 72%, or +50, at the height of the pandemic last year to 53% or +12 last week. Even so, the same poll showed the SNP remains twice as popular as the Tories and Labour. Last week Sturgeon told the BBC political editor, Laura Kuenssberg, that she recognised the SNP had “still got a job to do” to build a majority in favour of independence: “I think we are much closer to that than ever before, but are we there yet? No.” Jackie Baillie, Scottish Labour’s deputy leader, said the £20 increase in the child payment was welcome but said Labour would be pressing for that to be doubled again to £40 next year in the next Scottish budget. “As it stands, this welcome development will not be enough to ensure we meet the statutory child poverty targets that the Scottish parliament has passed,” she said.