Opposing landlords are attempting to prevent Wilson Bowden's plans for a million sq ft (92,900 sq m) retail development at the former Ravenscraig steelworks site, south of Glasgow.

Standard Life and Land Securities have lodged a legal challenge against the Scottish Executive's decision to designate Ravenscraig as a town centre in its own right.

Standard Life and Land Securities say they support the regeneration of the steelworks site. However, they say that by amending the Glasgow and Clyde Valley Joint Structure Plan to accommodate the development, Scottish ministers are contradicting their own planning guidance note NPPG8, requiring all new retail and leisure development to take place in existing town centres.

Wilson Bowden was selected by steel giant Corus to create what is effectively a new town at Ravenscraig, with housing and business parks as well as a retail mall. It has been in talks with US developer Mills Corporation - owner of the 2 million sq ft (185,800 sq m) Xanadu development in Madrid - about sharing the retail element of the scheme.

However, the objectors say the Ravenscraig mall will suck life from existing Lanarkshire centres, such as Hamilton, East Kilbride and Motherwell, with its impact also being felt in more distant town centres, including Stirling, Falkirk and Livingston.

Land Securities regional director David Smith said: 'We have worked within the tight constraints of NPPG8 for many years. Our investment decisions have been based upon the clear understanding that planning policy, at national as well as local level, is designed to protect existing town centres. Calling Ravenscraig a town centre to allow one million square feet of additional floor space simply drives a coach and horses through the system'.

The case is unlikely to reach court before the second half of this year.