Six major property developers have entered the battle with Australian giant Westfield to redevelop an ageing south London shopping mall, the latest twist in a growing wrangle between the Whitgift Centre's owners.

Westfield, which opened a mall near the London Olympic park to great fanfare last autumn, said in November the 42-year old site in Croydon would become its third large London centre after an exclusive deal with the Whitgift Foundation, the freeholder and 25 percent leaseholder.

However, the decision -- publicly welcomed at the time by London Mayor Boris Johnson -- sparked an angry response from the 1.2 million square foot mall's other two leaseholders, Royal London Asset Management and Irish Bank Resolution Corp (IBRC), formerly Anglo Irish Bank, who said they were not consulted on the plans.

Royal London and IBRC have now drawn up their own shortlist of seven developers, including Westfield, to undertake a major refurbishment and possible expansion of the site, two sources familiar with the process told Reuters.

British Land, Land Securities, Hammerson, Lend Lease and Delancey are on the list, which was put together without any input from the Whitgift Foundation, the sources said. The developers will present their proposals this week.

Large UK shopping centres that dominate their catchment areas are highly prized by property investors as they have so far weathered the tough retailing climate better than the rest of the UK.

The Whitgift Centre's Croydon location was under-served by high quality retail and leisure facilities, Westfield said in its November 11 statement, adding a major retail scheme had the potential to serve over three million customers.

Westfield declined to comment on the expansion of the tender process.

Any decision will need to be rubber stamped by the Whitgift Foundation. What happens if the foundation rejects the proposal was still under discussion one of the sources said, describing the situation as a stand-off.

IBRC and Royal London confirmed a selection process was underway. All parties declined or were unavailable to comment on the identity of potential developers.

The two leaseholders will offer the winning developer a minimum 25 percent share of their joint 200 million pound stake and responsibility for managing the centre. They expect to pick a developer by end-February.

Westfield, the world's second-largest mall developer by

market value, manages 124 shopping centres globally with total assets under management at more than A$59 billion, the company said in August.

(Reporting by Brenda Goh; Editing by Tom Bill and Jodie Ginsberg)