Arsenal were today bracing themselves for the shock departure of managing director Keith Edelman, a key figure behind the club's successful move from Highbury to Emirates Stadium.

It is believed Edelman will make a formal announcement tomorrow and his exit will fuel fears of an escalation in the battle for control of the boardroom that could impact upon Arsene Wenger's plans for next season.

Edelman joined Arsenal in 2000 following a highly successful career in business which included serving as managing director of Carlton Communications and as group chief executive of the Storehouse company that embraces Mothercare and British Home Stores.

He exploited his business acumen to oversee the rebranding of Arsenal, taking in a sponsorship deal with Nike reported to be worth £130million over 10 years and the signing of a 15-year contract worth £100m with the Emirates airline which included naming rights to the club's impressive new north London home.

However, Edelman's strong belief in the self-sufficiency of Arsenal was at odds with the trend for super-rich individuals to buy control of clubs, with Roman Abramovich at Chelsea being the prime example.

Arsenal are being courted by another Russian billionaire, Alisher Usmanov, who already boasts a 25 per cent shareholding, and American sports team owner Stan Kroenke.

In a recent interview, 57-year-old Edelman said: "There are two basic models in football ownership, the business model and the benefactor model.

"The trouble with the benefactor model is that it only works as long as the benefactor continues to be interested and invests his money.

"If that finishes, the whole thing falls away. That is not a long-term robust strategy. With the business model, and this is the one that works, everything must be run from within the club's own resources. The idea that you need to have a billionaire owner is tempered a bit by looking at the experience of a club like Liverpool."

The Anfield club, beaten by Chelsea in last night's Champions League semi-final, are in a state of turmoil as American businessmen George Gillett and Tom Hicks battle for control.

The problem confronting Arsenal is that while income from broadcasting and match-day revenue has grown substantially, an investigation conducted by the influential Arsenal Supporters' Trust suggests that manager Wenger will have a war-chest of only £25m to spend on players next season.

Edelman was due to meet the Trust on 12 May when questions were bound to be raised about Arsenal's failiure to win any silverware for the past three seasons. The belief among supporters is that £25m will not enable Wenger to compete against Champions League finalists Chelsea and Manchester United.

Trust members were also set to quiz Edelman on commercial and retail revenue streams which they perceive to be crucially weak compared to other top Premier League clubs.

Edelman's post at Arsenal is understood to be worth £750,000 but his career record suggests the keen tennis player and antiques collector will have no trouble finding another top job.