The German government plans to ban child marriages, after the refugee crisis saw an influx of married couples into the country in which at least one spouse was under 18.

The new law, that is set to be approved by the German parliament in July, is designed to help protect exploited minors, especially girls, by annulling foreign marriages.

It gives youth welfare workers the authority to take girls into care, even if they were married and, if necessary, separate them from their husbands.

"Children do not belong in the marriage registry office or the wedding hall," said Justice Minister Heiko Maas in a statement sent to AFP.

"We must not tolerate any marriages that harm minors in their development."

"The underaged must be protected as much as possible," he said, adding that the new law will not affect the refugee or residential status of married minors.

In Germany, marriage is legal if one spouse is 16 or 17 and the other 18 if special permission is gained from a family court. Under the new law, the minimum age at which a person can marry will be raised to 18. Exceptions will be made in cases where spouses were married as children but are now adults and want to remain married.

Those attempting to marry minors in traditional or religious non-state ceremonies will face fines.

There were 1,475 married minors registered in Germany in July, 2016, with 361 of them aged under 14, according to the latest figures released after a parliamentary request.

The number of married minors in the country rose significantly in the wake of the refugee crisis, when more than a million asylum seekers and immigrants entered Germany, many fleeing conflict in Syria.