A federal judge is set to rule to demand that the US state of Ohio must recognise out-of-state same-sex marriages.

Judge Timothy Black’s official ruling is expected on Monday, but he announced the intention to do so last week.

Attorney General Mike DeWine has already said it will appeal against the ruling when it is made.

Black already in December issued a limited ruling which ordered the state to recognise same-sex marriages for death certificate purposes.

An Ohio US Representative last week called for the impeachment of Black for his intention to strike down the ban.