Unqualified retirees and trainees are filling a gap left by teachers exiting the profession due to rising class sizes and difficulties with foreign languages of new pupils, teachers groups in Germany have warned.

The “dramatic shortage” of teachers is the worst Germany has seen for nearly three decades, Heinz-Peter Meidinger, president of the German Teachers Association, said in comments published across German media on Monday.

"There are currently around 10,000 teaching positions left unoccupied, and there are about 30,000 posts that are provisionally filled by non-teachers, newcomers, retirees and students," Mr Meidinger said.

In Berlin and Saxony the situation is particularly bad, according to Mr Meidiner. "In Berlin, 70 per cent of newly hired primary school teachers are without any educational background," he told the Passauer Neue Presse newspaper. He added that a “whole generation” of school pupils will be harmed by the shortage.

Teachers in the country are under increasing pressure, Marlis Tepe, president of the The German Union of Education and Science (GEW) told Germany’s tagesschau24 television channel earlier in August. The job has become more demanding, with bigger classes being filled with children who are at different levels, Ms Tepe said. Many children also have language difficulties, she said. As a result, a lot of new teachers don’t last long in the profession.