UBS Warburg is preparing to bid for the core trading arm of crippled energy group Enron, according to a source close to the bank.
But the bank is some weeks away from making a proposal to bankruptcy administrators, the source said.
Rivals JP Morgan and Citigroup may also be preparing offers for the business that dominated world energy trading until it collapsed amid mounting debts this month, the source said.
"There is still some way to go and internally some things to pass. It is still at a very early stage".
A serious financial bidder could be key to any rescue effort for Enron, which will need strong financial backing before trade counterparties will do business with it again.
The loss of confidence in its creditworthiness among trade counterparties helped bring the company to its knees earlier this month. Officials of all three banks declined to comment.