UBS prefers to focus on its own wealth-centric strategy and is reluctant to take on risks related to Credit Suisse, the report said, as the smaller rival seeks additional time to complete its restructuring efforts after receiving financial support from the Swiss central bank.

UBS and Credit Suisse declined to comment on Reuters' requests for comment.

Wall Street bank JPMorgan on Wednesday said that Credit Suisse's takeover by another lender, probably UBS, was the most likely scenario for the embattled bank.

Credit Suisse sought to restore investor confidence on Thursday by borrowing up to $54 billion from the Swiss National Bank after a slump in its shares had intensified fears of a global banking crisis set off by a collapse of two mid-sized U.S. lenders.

(Reporting by Urvi Dugar in Bengaluru; Editing by Mark Potter and Paul Simao)