Managers at Tower Hamlets Council say "cultural background" is a significant consideration when making foster placements.
But they say other factors also have to be taken into account.
The girl's case hit the headlines following reports she had been placed with a Muslim family and encouraged to learn Arabic.
A family court judge re-analysed issues on Tuesday - at a private family court hearing in London - and said the youngster should move to live with a relative.
Debbie Jones, the council's corporate director of children's services, said: "Once the decision was taken to place the child into temporary care, we had to find the best placement available at the time.
"While cultural background is always a significant consideration in making this decision, so too are other factors including remaining in the local area to promote contact with the child's family and for the child to continue at the same school in order to give them as much stability as possible."
She said the priority was to place a child in a "safe and loving environment" and added: "Our foster carers are qualified people from different backgrounds, with vast experience of looking after children.
"They represent the diverse make up of our borough which is a place where people of all backgrounds get on with one another."
A council spokesman said staff had ''always been working towards the child being looked after by a family member".
He said there had been ''inaccuracies'' in media reports and the girl had been temporarily placed with an ''English-speaking family of mixed race''.
Judge Khatun Sapnara re-examined the case at the family court hearing on Tuesday.
The judge decided that the girl, who has not been identified, should leave her foster placement and move to live with a grandmother.