Schoolchildren in France are being taught that the EU only has 27 member states, in an indication that the country has already begun to purge the UK from the bloc.

Britain has been removed from maps of the union in a popular educational guide, the Aedis “petit guide”, which shows all of the other 27 member states shaded in a different colour with each of their national flags – while Britain is left blank with no flag.

The guide to the EU, which is aimed at schoolchildren, was first published in January 2007 but was “updated” in May 2017, apparently to reflect Britain’s departure, according to the publisher’s website.

It states: “The European Union brings together 27 countries of Europe in economic and political terms, in order to avoid wars and to defend democracy, human rights, prosperity and peace more effectively.”

The guide also claims that “numerous other countries in Europe want to join” and observes that “institutions and treaties must be adapted in view of this enlargement.”

It continues: “Every day, the European Union allows all its nationals to study, travel, live and work in the country of their choice amongst the member states, all this without the need for passports or borders.”

It comes as a number of French politicians and officials indicated that France is taking advantage of Brexit, by launching a charm offensive to attract British banks and business and encouraging French workers who have previously moved to London to return to Paris.

French Finance Minister Bruno Le Maire announced earlier this week that France would set up a special court to handle English law cases for financial contracts after Britain leaves the EU, in a bid to attract banks.

Valérie Pécresse, chairwoman of the Paris regional council, meanwhile told The Times: “Boris Johnson and David Cameron said to anyone prepared to listen they were rolling out the red carpet for the French.

“Now we are rolling out the tricolour carpet. Our first aim is to get back the French people who moved to London.”