Labour has vowed to force a vote over the government’s “totally insufficient” plans to help pupils catch up on learning lost during the pandemic, as Tory MPs demand an urgent rethink of the programme.

Senior Tories are calling for a wider programme that could include trials of a longer school day and extended physical education and wellbeing activities, to help children in England readjust after time out of the classroom.

Amid suggestions that education secretary Gavin Williamson had been fighting for a significantly greater catch-up package within government, his department published an analysis on Friday that showed that much of the past decade’s progress towards reducing the attainment gap for disadvantaged children could have been lost during the pandemic.

Labour is planning a vote following the resignation of Sir Kevan Collins, the government’s education recovery commissioner, after he condemned plans for a £1.4bn recovery fund as woefully short of what was needed. He said the figure betrayed “an undervaluation of the importance of education”.

Collins had drawn up plans that would require a £15bn learning recovery fund to be spent on teachers, tutoring and an extended school day. His proposals included 100 extra hours of teaching per pupil to address lost learning.

While Labour intends to embarrass the government with the vote, Tories concerned about the catch-up plan said they were likely to abstain rather than rebel. Some already believe the backlash will lead to more money being announced in the coming weeks. Williamson has suggested that he is in favour of longer school days, but is awaiting research on the issue.

Kate Green, the shadow education secretary, said that children had been “treated as an afterthought” in the government’s pandemic planning. “Kevan Collins’s resignation makes it clear that the government’s education recovery plan is totally insufficient to help every child bounce back from these impacts of the pandemic,” she said. “Conservative MPs will now have the chance to step up and vote for our children’s futures.”

Paul Whiteman, general secretary of school leaders’ union the NAHT, also said that pupils seemed to be “very far down the government’s list of priorities”. Labour said the economic impact of lost learning was at least £100bn, with a potential loss to the economy and country of £420bn. It has drawn up its own proposals for a £14.7bn catch-up plan, including breakfast clubs for every child, mental health support and more small group tutoring for pupils who need it.

A government spokeswoman said: “We have committed to an ambitious, long-term recovery plan, including an investment to date of over £3bn and a significant expansion of our tutoring programme, to support children and young people to make up for learning lost during the pandemic.”