Labour has risked stoking fresh controversy by accusing Rishi Sunak of not thinking that schools should be safe.
The party’s latest attack ad comes amid the mounting scandal over schools being forced to close because of crumbling concrete.
It has echoes of the infamous poster from earlier this year which accused the prime minister of not wanting sex offenders to be jailed.
That sparked a furious row, with Labour being accused of “gutter politics”.
Like that one, the new ad also has a picture of the prime minister alongside his signature.
It states: “Do you think your child’s schools should be safe? Rishi Sunak doesn’t.”
The ad goes on to claim that when he was chancellor, Sunak cut spending on school rebuilding by almost half, and says the Tory/Lib Dem coalition ditched Labour’s schools for the future programme in 2010.
The advert adds: “The Tories ignored Labour’s warnings time and again - now our children are paying the price with crumbling schools.”
A Labour source told HuffPost UK: “It’s a timely reminder as parliament returns that the Tories can talk all they want - they can’t hide from the fact their disastrous running of the country over 13 years is hurting families across Britain.”
It emerged on Thursday - days before the end of the summer holidays - that more than 150 schools had been ordered to either partially or completely close because the “RAAC” concrete used to build them is at risk of collapse.
Education secretary Gillian Keegan said the government was taking a “cautious approach” to protect pupils and staff.
She said: “Children should attend school as normal in September, unless families hear differerently.”
But her Labour shadow, Bridget Phillipson, said: “This is an absolutely staggering display of Tory incompetence as they start a fresh term by failing our children again.
Ministers now fear that other public buildings, such as hospitals, could also be affected by the scandal.