A court in Japan has ruled that a law denying Japanese nationality to children of unmarried Japanese men and foreign women is unconstitutional.

The law refuses nationality to such children unless the father recognises the child as his before the birth.

The court said it was unconstitutional not to grant Japanese nationality just because the parents were unmarried.

The Tokyo judge was ruling in a case brought on behalf of nine children of Japanese fathers and Filipina mothers.

Correspondents say Japan is believed to have hundreds of such illegitimate children.

BBC News