UPDATE 1-U.S. and UBS seek delay in closely-watched trial

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MIAMI, July 12 (Reuters) - The U.S. government and UBS AG (UBSN.VX) (UBS.N) asked a federal judge on Sunday to delay the opening of a closely-watched trial, as they seek to resolve their dispute over U.S. demands for the identities of thousands of wealthy Americans suspected of using the Swiss bank to dodge taxes.

The request, in a joint court filing, came as the clock ticked down to the trial set for 9 a.m. EDT 1300 GMT) Monday in Miami, where U.S. authorities had been expected to move forcefully to pry the lid off Switzerland's much-vaunted tradition of bank secrecy.

In their filing. the U.S. Justice Department and UBS asked that the start of the trial be postponed until Aug. 3, giving the Swiss and U.S. government time "to continue their discussions seeking a resolution of this matter."

There was no immediate response from U.S. District Court Judge Alan Gold, who is presiding over a civil lawsuit against UBS and was to have begun hearing arguments about why he should force Switzerland's best-known bank to disclose information on up to 52,000 wealthy U.S. clients suspected of using it to evade U.S. taxes. (Reporting by Tom Brown; Editing by Vicki Allen)