AER Rianta's involvement with Birmingham International Airport could be in jeopardy as the airport's £400 million sterling expansion plans now seem likely to go before a lengthy public hearing.

Aer Rianta was selected as the preferred bidder for a 40 per cent stake in the airport last September and is currently in negotiations with seven local councils which collectively own it.

But earlier this week the planning committee of one of the councils, Solihull, deferred taking a decision on the development, and placed a series of strict conditions or the application.

The full Solihull council will meet next week to consider the application. It appears likely that, should the full council endorse the committee's decision, the airport will appeal, which would lead to a public inquiry on the matter.

An Aer Rianta spokesman said it was "not appropriate" to comment on the matter "at this stage". However, it is thought likely Aer Rianta and its partner NatWest Ventures may choose to reconsider their position if the airport's expansion plans are seriously curtailed.

The 40 per cent stake in the airport is expected to cost about £60 million. A spokeswoman for Birmingham Airport declined to comment on the planning row as she said the airport wad "in limbo" until next Tuesday's full council meeting.

The new conditions imposed on the planning application include no night flights between 11 p.m. and 6 a.m. and an agreement from the airport's owners not to extend the main runway within 30 years.

The 13 councillors on the planning committee also want to know how much backing the airport's owners would put into extending the light rail system to the airport, which is nine miles south of the city centre.