By james art German Ambassador Miguel Berger and French Ambassador Hélène Duchesne told The Times they wanted international schools to be excluded from plans to impose a 20% VAT on private schools.
From January, the government plans to scrap VAT exemptions and business relief for private schools to enable funding for 6,500 new public school teachers.
Independent schools do not currently have to charge 20% VAT on their fees as there is an exemption for the supply of education.
Mr Berger said Deutsche Schule London, based in Richmond, has around 900 pupils and “between 20 and 25 per cent could be forced to leave the school” if the change is introduced.
He added: “The German state covers 30 percent of the school’s costs and 50 percent of the investment, so there is a lot of state funding going into the school.
“For expats who come here for two, three or four years and want their children to go back to the national system, their only option is to go to these schools.
“We would really like to see the British Government recognize the importance of these schools – not just to our political and cultural relationship, but to the people it will affect.”
Mr Berger said company executives investing in the UK “should know they can send their children to a German school”.
Critics of the VAT change have warned of the short timeframe and the risk of unintended consequences, including the impact on children with learning difficulties who attend specialist independent schools and military families.
There are 11 schools in the UK accredited by the French Ministry of Education, nine of which are in London.
Ms Duchesne said these schools would be “weakened” by the VAT change.
She added: “We are not asking for an exemption: we are not the target of this VAT measure.
“Our schools differ from the target ones because we follow special courses to prepare for the French language exams.
“These parents don’t have a plan B because other schools don’t follow the French curriculum.”
She said 6,300 pupils could be affected across the UK, adding that the change was “not in line with the restoration of our relationship which the British government has been pushing for”.
Ms Duchesne said VAT “could also be a problem for our companies because they need these schools for employees coming to work here”.