At least €7bn is needed for urgent school maintenance and repairs, according research by Nos television for the education ministry.

Some 1,100 school heads took part in the survey and 70% said work needs to be done on their school buildings. The most urgent problems involve improving the heating and ventilation systems, solving problems with doors and windows and improving insulation.

The Netherlands has 6,855 primary and 1,222 secondary schools.

A spokesman for the ruling VVD told the broadcaster school maintenance is an issue for local councils.