Woolworths have seen their shares increase after the troubled retailer said it had rejected a takeover bid for its 815 stores from Iceland.The offer from a consortium headed by Mr Walker of Iceland, was considered too low. Icelandic investment group, Baugur, has a 10% stake in Woolworths and also owns Iceland.Mr Walker intends to take control of Woolworths' retail sites, but only if the firm agrees to cover its pension deficit, valued at £48.2m in its latest annual report, and retains its £142m debt.