Liz Truss is being urged to offer a lifeline to hard up families by extending free school meals to all pupils.
Labour MP Kim Johnson demanded immediate action from the new Prime Minister to prevent kids from freezing and starving this winter as the cost of living crisis spirals.
All pupils in English state schools are currently entitled to free lunches up to the end of Year 2.
After that, they are only eligible if their parent or carer receives certain benefits. Families on Universal Credit can only get free school meals if their annual income is less than £7,400, without including benefits.
There has been a growing clamour from teachers, unions and campaigners to expand free lunch provision, which has been committed to in Scotland and Wales.
Speaking in Parliament, Ms Johnson said: "If the new Prime Minister is to prevent children from freezing and starving this winter, rolling out universal free school meals must be a key cornerstone of any emergency support plan.
"Instead of a real living wage and a welfare system that supports people out of poverty, we have a crisis of insecure work and poverty pay and a welfare system that drives people into destitution.
"Make no bones about it, we are facing an unprecedented humanitarian crisis."
The Liverpool Riverside MP warned that hunger was holding back poorer pupils, who are already more likely to lag behind their peers in class.
She said: "It’s scandalous that even at this young age, for most of them their futures have already been decided."
Around 1.9 million pupils in England are eligible for free school meals, according to the latest figures. This equates to 22.5% of pupils, up from 20.8% in 2021 as the pandemic pushed more families into hardship.
A recent report from the Food Foundation revealed that around 2.6 million children live in households that missed meals or struggled to access healthy food.
Levels of insecurity in households with children have risen by over 40% since the start of this year, Ms Johnson said.
The Labour MP added: "We cannot lose sight of the human impact of not feeding our children, or of choosing an arbitrary threshold to decide who deserves to go hungry and who deserves to be fed."
Education Minister Kelly Tolhurst said there were no plans to extend universal provision but added: "We will continue to keep free school meal eligibility under review to ensure that meals are supporting those who need it most."
