A “pioneering” Greenwich free school with bags of support from parents and the government is desperate to find a building for its September launch.

There are around 100 families hoping for the International Academy of Greenwich (IAG), which will specialise in languages, to open this autumn but they say “time is running out” to find a site.

The oversubscribed secondary school may fail to open for the second year running if no building is found which supporters say is partly down to resistance from Greenwich Council and the Church of England.

Father-of-four Andy Hier, whose son Oliver Hier, 11, is set to go to the school, said: “Time is running out. There are 100 odd families who were really hoping this was going to happen and naturally parents have to look elsewhere which is a shame.

“We have everything we need from the top of the government to parents, just apart from a building.”

The 50-year-old self-employed IT contractor at a law firm, who lives in Blackheath Park, set up a petition to gain support for the site which can be found at change.org

The Department for Education has backed the school’s vision to offer globally-known qualification The International Baccalaureate (IB) – currently mainly available at fee-paying schools.

Chief executive of IAG Nick Zienau said: “We are pioneering something.

“There is clearly a demand for this school. There are so many bilingual families in Greenwich and the idea is being bilingual should be normal, you shouldn’t see it as a foreign language, but that children have more than one native language.

“There is enormous interest from all over Greenwich including the poorest parts because of the IB's vision and we believe we can provide this for all people, not just for an elite who can afford £25,000 every year.”

He added: “Our frustration is with a lack of active support locally, both politically and from the church leaders.

“But the support of the parents demonstrates the strength and need for this school and we are going to carry on until we find such a site.”

The school’s board has eyed up Blackheath Bluecoat Church of England secondary school which is closing in July but the Diocese of Southwark says it has not decided on the site’s future.

A Diocese of Southwark spokeswoman says Blackheath’s Bluecoat’s school will still be in use until October for administrative tasks.

She added:“The trustees of the site and buildings are considering the best use of this asset in order to further the objects of the Southwark Diocesan Board of Education.

“No final decision has yet been made concerning this and thus the school site is not currently available for sale or rent.”

A Greenwich Council spokesman said: “We have received no planning application and so have had no involvement in the school’s choice of site.”

He says the council has alerted the school of suitable sites but they were not judged to be in the right location by the school.

He added: “The council is surprised by the inaccurate assertions being made by IAG with whom we have been completely open about our plans.”