For the second time in a month, last week cleaners at Highgate Wood School picketed a parents’ evening.

A number of cleaning staff, who are employed by contractor the Lakethorne Group, have been taking industrial action over the company's refusal to pay them the London Living Wage.

The striking cleaners - part of the Cleaners and Allied Independent Workers Union (CAIWU) - also have grievances relating to their schedules, holiday pay, and a lack of "adequate materials" being provided to do their jobs.

Brian Castillo, 25, a supervisor who works at the school, told this newspaper: "We are here because of payments. There are some people paid differently for the same work, They don't pay holidays. This means we are stuck when the school is closed. Many people have to have another job.

"I have to pay my rent, my transport. There are people here who just have this work, they just get no pay."

Some parents attending the open evening were supportive of the strikers. One, Hugo Glendinning, said: "I think it's great, they should strike. The lowest paid workers in our society get so little."

Another, Helen Clanton, said: "It's wonderful for the cleaners that they are trying to be paid the living wage. I really respect what they are trying to do."

The school's headteacher Patrick Cozier said; "We are still actively trying to resolve matters at the earliest available opportunity. We've already agreed to participate in any three-way talks with the CAIWU and Lakethorne under the auspices of ACAS. We expect talks to resume as soon as possible after the Christmas break."

In November, a spokesperson for the Lakethorne Group said it was "continuing to work closely with our employees in order to find a solution to the ongoing pay discussions", but the outsourcing company has not responded to a subsequent request for comment from this newspaper in light of the ongoing action.