School uniforms will need to be ‘inclusive’ and ‘gender neutral’ under the Liberal Democrat’s plans.
The party’s manifesto, released today, also said uniform policies will need to “suit different budgets”.
It would bring English schools in line with Welsh plans to move to gender-neutral uniforms in September.
The manifesto states a Liberal Democrat government would “require inclusive school uniform policies that are gender-neutral and flexible enough to suit different budgets, and provide training for school staff on how to review and improve their uniform policies”.
The policy appears alongside a pledge to introduce gender-neutral passports, which would have an “X” option as well as traditional “M” and “F” identifiers.
Jo Swinson’s party also wants to “challenge gender stereotyping” and work with schools to “break down outdated perceptions of gender appropriateness” in some subjects.
Government research published earlier this year show the proportion of boys whose favourite subject is in the “STEM” category - science, technology, engineering and maths - is nearly double that of girls.
The Liberal Democrats would also promote pastoral leadership in schools and tackle bullying on the basis of gender, sexuality and gender identity.
The party has also pledged to tackle “early sexualisation” by promoting positive body image with schools.
The pledges are among a raft of promises made in the manifesto, called “Stop Brexit, Build A Brighter Future”, which was released today.
It reiterates that the party would revoke Article 50 and remain in the EU if it lead a government, and will otherwise aim for a second referendum.
Other key policy announcements focus on a so-called “Remain bonus”, which the party says would allow £50 billion to be spent on public services.
It wants to spend £130 billion investment in infrastructure, employ an extra 20,000 teachers and restore corporation tax to 20%.