Germany’s highest court has refused to rule on allowing same-sex couples in civil partnerships the right to adopt children.

On Friday, the Constitutional Court in Karlsruhe, south-west Germany, dismissed on procedural grounds a request from a Berlin district court to rule on the matter.

Deutsche Welle reports the case was introduced by a gay couple who want to adopt their two former foster children, who are now adults.

A district court had stayed the proceedings in March 2013 and submitted the case to the Constitutional Court.

Judges today said the submission did not meet the formal requirements and dismissed the case, without commenting on the issues surrounding it.

The decision follows a landmark ruling by the court in February last year, in which it granted those living in civil partnerships the same legal rights as married couples when it came to adopting the biological children from one partner.

However, the ruling only meant that same-sex couples could adopt the same child on an individual basis and not as a couple and they still cannot adopt unrelated children.

Germany’s Constitutional Court called for the tax system to treat civil partnerships equally with marriages in May 2013 – a demand which Chancellor Angela Merkel had previously resisted.

Same-sex marriage remains illegal in Germany.