The district council deliberately withheld evidence on which it has relied to support its case against the railfreight terminal, according to the barrister representing the developer Helioslough.

During the cross-examination of the district council's planning expert John Hargreaves, Helioslough's barrister Martin Kingston accused the council of concealing its independant alternative sites study until after the developer's proof of evidence had been disclosed.

Mr Kingston said: "The first time the alternative sites study was revealed was when proof of evidence was disclosed. At no stage prior to the delivery of that proof of evidence did the council disclose that it had undertaken such a study."

Helioslough's alternative sites assessment examines only five locations in the north-west sector, concluding that the former Handley Page airfield is the most suitable.

But the council's alternative study, presented to the inquiry on Tuesday, considers about 20 sites across the whole of the Home Counties, and concludes there are at least six better ones, including locations in Kent, Surrey and Essex. Mr Kingston referred Mr Hargreaves to the inquiry's concord which states there should be no surprises and critical dialogue should be maintained between both parties throughout the case.

The issue is likely to be critical, as the company's first appeal would probably have succeeded but for flaws in its sites assessment, which it claims now to have rectified.