The Barclay brothers were considering their options today after a private deal for control of the Telegraph newspaper group was blocked by a US court.
A US judge ruled that deals made by Lord Black of Crossharbour over the future of the Telegraph Group were invalid because the media baron had consistently breached his duties to the titles' owner, Hollinger International.
This scuppered a deal with Sir David and Sir Frederick Barclay to purchase Lord Black's stake in Hollinger Inc, which would have given them 70% of voting rights in Hollinger International.
A spokesman for the Barclays declined to comment on the court ruling, but speculation in the City centred on their next move in the long-running takeover saga.
Judge Leo Strine, of the Chancery Court in Delaware, said his decision did not stop the Barclays pursuing the Telegraph.
But he ruled that any offers for the titles had to be made as part of the formal sale process managed by investment bank Lazard.
This process has seen formal offers from investment groups Candover and Collins Stewart, while Express newspapers owner Richard Desmond has also confirmed a bid. Another media heavyweight thought to be participating is the Daily Mail & General Trust.
Analysts said the ruling was a setback for the Barclays but expected them to have drawn up contingency plans in case the US court ruled against Lord Black.
Attention was focused on whether they lodged a bid with Lazard ahead of the deadline for offers earlier this month, and how much they were prepared to pay.
Justin Urquhart Stewart, of Seven Investment Management, said bidding for the titles could now top £600 million.
He said: "It's open season now. It could more than double the value of the Telegraph group if there is a clear auction.
"The Barclay brothers have a wealth of private property money behind them and their pockets could go much deeper to secure a deal."
The Barclays, who own The Business and several Scottish newspapers, would have to win over Hollinger International shareholders angered by their willingness to do a deal directly with Lord Black.
Uncertainty over the future of Hollinger International, which also owns the Chicago Sun-Times and the Jerusalem Post, has been present since November when it appointed Lazard to "review and evaluate its strategic alternatives".
David Buik, of financial bookmakers Cantor Index, said the ruling was a serious setback for the Barclays.
He now rates Mr Desmond as the likely winner of the race for the Telegraph titles.
Mr Desmond currently has a share in a joint venture printing plant with the Telegraph group in east London.
Mr Buik said: "I can't believe that the Barclay brothers have just stood there and folded their hands because the evidence that has been filtering through before the Delaware court case has been pretty grim.
"If they've sat back and done nothing in submitting a bid, then I would be very surprised. They have said consistently they had a legal agreement with Lord Black but one suspects that they also have some contingency plans."