BERLIN: Germany's highest court has delivered a ruling that strengthens gay couples' adoption rights.

The Federal Constitutional Court ruled on Tuesday that one member of a civil partnership should be able to adopt the partner's stepchild or adopted child. Until now, they could only adopt a partner's biological child.

The court ordered the government to draw up new legislation by next June. It said the German constitution doesn't justify ruling out one partner adopting the other's adopted child.

Volker Beck, a senior lawmaker with the opposition Greens who is openly gay, greeted the ruling as "a breakthrough in equal treatment."

Germany has allowed same-sex couples to register civil partnerships - that legally fall short of formal marriage - since 2001. Same-sex couples are not allowed to adopt unrelated children.