New grammar rules and new spellings are being introduced in an attempt to simplify the language.

But critics say the changes spell trouble and polls indicate only 16% of people plan to follow the new rules.

The legally binding Rechtschreibreform changes the spellings of hundreds of words.

Print media will use the new language rules in Monday's editions.

Many of the changes Germanise words of foreign origin. Ketchup becomes Ketschup and Mayonnaise is now Majonaese. and Telephon changes to Telefon.

Karin Frank-Cyrus, director of the Society for the German Language, said: "Everyone will quickly get used to them and finally realise what relief the reform brings with it."

But opponents are calling for the reform to be overturned and hope to force a referendum on the issue.

Matthias Draeger, of the anti-reform campaign, said: "It will take about two to three years for the public to realise how stupid the changes are and to demand they be rescinded."