Rafael Benítez gave only a cautious welcome yesterday to Tom Hicks's and George Gillett's commitment to sell Liverpool as he admitted experience had taught him to be wary of the co-owners' promises.

Hicks and Gillett signalled the beginning of the end of their turbulent three-year reign by appointing the British Airways chairman, Martin Broughton, as Liverpool's new independent chairman with a brief to oversee the sale of their entire stake with immediate effect.

Broughton announced his arrival by pledging money for new players and support for Benítez, who has endured a troubled season at Liverpool but is coveted by other clubs. "Rafa is a good manager, we want him to stay and he's under contract to stay," said the Liverpool chairman.

Benítez's response was guarded, however. The manager declined to commit his long-term future to Anfield and admitted his outlook has not altered since he claimed he had taken the club as far as he can – without new investment – before the Europa League defeat of Benfica.

"You always have to be positive and believe things will improve, so it is good news and hopefully it will be true," said Benítez. "My experience says it is better to wait and see what happens." Asked if he felt more optimistic as a result of the co-owners' intention to sell, he replied: "At this moment it is more or less the same [as before Benfica]. I have to be honest. My concern at the moment is whether Fernando Torres is fit or not and preparing the team for next week's games against West Ham and Atlético Madrid."

Broughton's arrival does at least end the paralysis that has hindered major decision-making inside the Anfield boardroom since the business relationship between Hicks and Gillett fractured in late 2007. A new five-man board has been proposed – comprising Broughton, Hicks, Gillett, the managing director, Christian Purslow, and the commercial director, Ian Ayre – and the Americans have bought time for the sale with a six-month extension to their refinancing deal with RBS and Wachovia.

"The club has the full support of its existing bankers for this process and has financing in place which will fully support the club's operations," read a statement.

Barclays Capital has been appointed to conduct the search for new investment. The co-owners had previously employed two banks, Rothschild and Merrill Lynch, to find buyers for a partial share in Liverpool. It is anticipated a 100% sale will be far more attractive to investors and interest has been expressed from groups in India, China and the Middle East. Broughton is said to be confident of a deal in the coming months but there are no guarantees of a sale.

"There should be no popping of champagne corks just yet," said a source close to the process. "A buyer has to be found for Liverpool first and the owners have to agree a deal." A £110m offer for a 40% stake, from the Rhône Group, has been the only official offer so far and the deadline on that deal passed last week.

Broughton said: "What is best for the club is somebody or bodies to come in and build the new stadium, make sure that the club is properly financed and that there is enough money available to take the club forward. I have looked at the stadium project and frankly there is an overwhelming financial logic to any buyer to proceed with the stadium. Any buyer would be crazy not to do so and they won't get to be the winning bid without the commitment to building the stadium. I think everybody concerned – fans, players and the manager – can all look forward to a very bright future."

Without a swift deal Benítez's transfer budget will consist of funds from the refinancing deal plus the sale of players such as Albert Riera and Yossi Benayoun. Hicks and Gillett value Liverpool at around £500m but whether they will lower their asking price remains a deciding factor. "Owning Liverpool Football Club over these past three years has been a rewarding and exciting experience for us and our families," claimed the co-owners, whose tenure has resulted in mass protests outside Anfield and prompted security operations on their occasional visits to the stadium.