Teachers at private girls’ schools have started industrial action in a dispute over pensions.

National Education Union (NEU) teachers at South Hampstead High School are striking against the Girls’ Day School Trust (GDST) proposal to withdraw from the Teachers’ Pension Scheme (TPS).

It is the first strike in the trust’s 149-year history.

Management say they feel the change is necessary to "support the long-term sustainability" of the trust.

The NEU claims that if the withdrawal goes ahead, teachers will be at least 20% worse off in terms of annual pension payments.

Hannah McDougall, head of history at the schools, said: “The alternative model that the GDST is proposing is going to be significantly financially worse and the only way that we can make up the shortfall in the pension is by contributing from our wages, and so effectively it is a pay cut."

About 50 members of the school’s teaching staff were striking on Thursday.

Hannah said: “Our position as teachers is that we are not radical people at all and none of us would take strike action lightly. This is a really important time for our students and we feel very conflicted about it."

The government implemented a 43% increase in employer contributions to the TPS in 2019.

Cheryl Giovannoni, chief executive of the GDST, said in a statement: “Sadly, the increase to the TPS employer costs has had a severe impact on our expenditure and has put us in a very difficult position.

“We care deeply about our teachers and would not have put forward these proposals unless we felt they were absolutely necessary to support the long-term sustainability of the GDST family of schools, enabling us to continue to provide an excellent and affordable independent education for our students, and at the same time ensuring teachers have a comfortable retirement.”

The GDST has 23 independent girls schools in England and Wales, with staff taking part in the six-day strike planned over February and March.

Over 70% of its teachers are members of the NEU.

Trustees will make a decision at the end of this month.