Immigrant children attending school in Germany should only speak German on school premises, a conservative lawmaker said.

Mario Czaja, secretary-general of the Christian Democratic Union, claimed that many immigrants are poorly integrated into society due to insufficient German language skills, and called for new measures at schools.

"Care should be taken to ensure that German is the main language spoken in schools. It is not acceptable for languages other than German to be spoken in the schoolyard," Czaja told the Die Welt newspaper.

The senior politician of Germany's main opposition party argued that more language experts, social workers and pedagogues should be hired for schools in places where many migrants live.

"Teachers and school administrations have to ensure that the students speak our language. Otherwise, parallel societies will develop starting from the schools," he claimed.

Immigrant organizations criticized Czaja's controversial remarks, which echoed previous suggestions by right-wing politicians, who called for banning speaking of foreign languages in the schoolyard.

Berin Arukaslan, co-chair of the Turkish parents association in Berlin-Brandenburg, has underlined that speaking their mother tongue is a fundamental human right, guaranteed by the constitution.

"We are strongly against this suggestion. This is nonsense," she told Anadolu Agency (AA), adding that German courts in the past ruled against introducing a ban on speaking the mother tongue in school corridors.

Two years ago, a court in the southern state of Baden-Wurttemberg dismissed disciplinary punishments against students who spoke their mother tongue in the playground, she noted.

"This court decision is very clear. Introducing such a ban is out of the question," Arukaslan said.

Some 27% of Germany's population has a migration background, and at elementary schools, 39% of all children are from immigrant families, according to the latest figures.