Scottish and Newcastle (S&N) has confirmed its partnership with Carlsberg in Baltic Beverage Holdings (BBH) is "untenable".
Chief executive John Dunsmore, in the role for just 20 days now, said the relationship was over following Carlsberg's joint bid for S&N with Heineken.
He said: "We can not return to the status quo.
"Instead of coming through the front door and bidding for BBH, they have crawled through the toilet window."
S&N said it was confident that it will win an arbitration case against Carlsberg, forcing the Danish brewer to sell its shares to S&N.
The brewer said it was looking for a minority partner to join it at BBH.
"In taking part in the consortium, Carlsberg has given S&N the chance to gain control of one of the developing world's most valuable assets."
Dunsmore said the 750p a share offer "grosly undervalued" the business. "My mother is putting a bid together at that level," joked Dunsmore.
S&N is still unhappy that Carlsberg is not allowing disclosure of future financial information regarding BBH.
Finance director Ian McHoul said he was restricted in his presentation to shareholders because of a "threatening letter from a former pen friend in Denmark".
Operations director Stephen Glancey, appointed to the board yesterday, refused to disclose if part of its operation would close as part of the deal to outsource 3m hectolitres of brewing to Coors.
"We have announced it today and the first thing we need to do is talk to our employees."
A consultation period will be completed in the early part of next year.