The foster parents, whose names were not reported, are members of the UK Independence Party, the BBC reported Saturday.
When social workers removed the children from the home, they allegedly accused the foster parents of belonging to a "racist party."
UKIP leader Nigel Farage -- who is also a member of the European Parliament -- called the situation "a bloody outrage" and told the BBC he was "very angry, very upset" at the decision made by Rotherham Council.
Joyce Thacker, the council's strategic director of children and young people's service, defended the decision.
"We always try to place children in a sensible cultural placement," Thacker said. "There are some strong views in the UKIP party and we have to think of the future of the children."
Council leader Roger Stone said the council was investigating the matter.