The Department for Education has refused to condemn parents who keep their children away from school despite promising a crackdown on truancy.
Schools are entitled to give children extra holidays as long as it is only for ten days a year, officials said.
Parents are "encouraged" to ensure their children attend school every day but they can keep them away from lessons if headteachers have agreed.
Cutting truancy has been a key aim of the Government's education policy and Labour has launched initiatives costing £885 million to boost attendance and behaviour.
However, figures earlier this month showed one child in 13 is a serial truant and Birmingham's inner-city constituencies had the worst truancy figures outside of London.
But children who miss school with the permission of the headteacher are not included in the truancy figures.
Birmingham City Council said it usually advised schools to refuse requests for extended holidays but an exception could be made for "families who wish to maintain links with their home country".
John Smail, head of education welfare, said: "The city council is very clear in its advice to schools - that parents should not normally take pupils on holiday during school term time.
"Schools will determine how they work with this guidance. In all cases parents who intend to remove their children from school for extended periods, for example to travel abroad, should first discuss their plans with the headteacher of their child's school. Any agreement should be the exception and schools should encourage parents to minimise absence."
But schools should be sympathetic to parents who wanted to send children overseas during term time, he said.
"We do understand that schools need to be sensitive to exceptional requests including those from families who wish to maintain links with their home country.
"In the case of Greet School, I understand their policy is consistent with the city's guidance and that holidays are encouraged to be wrapped around existing school holidays. Attendance has been improving at Greet by the school working with families, ensuring only one such request is approved throughout the child's primary education and any pupil who fails to return as agreed is removed from the school roll."
A DfES spokesman said: " We encourage parents, wherever possible, to book holidays during the school holiday period - every day in school counts.
"A term-time holiday can mean that children miss important school time and coursework, and it can cause disruption to teaching and lesson planning for the rest of the class. The ten days leave of absence in any one year should only be used for exceptional reasons."
Last night the schools were backed by their local MP, Roger Godsiff (Lab Sparkbrook and Small Heath).
He said: "As long as the school feels comfortable with the arrangements then as far as I'm concerned, that is fine.
"Allowing families to take children overseas in certain cases is fully in line with the council's guidelines."