REFILE-PREVIEW-Swiss in fresh push for UBS tax settlement

(Corrects word "day" in third paragraph) * U.S. status conference on UBS due on Wed 1300 GMT

* Talks could drag until late Sept if deal not reached

* Settlement may not be the end of U.S. tax litigation

* Swiss international tax treaties face referendum

* UBS shares down 1.4 pct

By Lisa Jucca

ZURICH, Aug 11 (Reuters) - Switzerland is striving to settle a long-running tax evasion dispute between UBS (UBSN.VX) (UBS.N) and the U.S. government that challenges Swiss banking secrecy, before a key pre-trial conference on Wednesday.

The U.S. is seeking the identities of 52,000 of the Swiss bank's wealthy American clients suspected of using offshore accounts to conceal assets and evade U.S. taxes. [ID:nLA660217] Miami Judge Alan Gold will ask the parties on Wednesday if they have reached a deal. If they haven't, negotiations will most likely drag on until Sept. 21, the next available day for a trial, prolonging a legal headache for UBS that has prompted wealthy clients to withdraw their savings.

A trial against UBS, the world's number two wealth manager by managed assets, has been postponed three times.

The dispute comes as governments around the world crack down on offshore tax evasion.

Earlier on Tuesday, Liechtenstein and Britain agreed to encourage Britons with secret accounts in the Alpine principality to voluntarily disclose billions of pounds of untaxed money [ID:nLB642083]

Switzerland itself is attempting to push through reforms needed to get off the Organisation for Economic Cooperation and Development's "grey list" of tax havens, but faces the prospect of a referendum on the issue.

The Swiss and U.S. governments have already reached an agreement in principle on the major issues in the UBS case, but talks have spilled into a fifth week as the two sides have been unable to settle legal details still standing in the way of a final deal.

UBS shares, which have rallied this month in anticipation of a settlement, were down 1.4 percent at 16.07 Swiss francs at 1409 GMT. Traders said investors were nervous on Tuesday because of uncertainty about the outcome of Wednesday's conference call between the judge and lawyers from UBS, the Swiss government and the U.S. Justice Department.

Investors expect a deal to involve the disclosure of some UBS client names and no fine for the Swiss bank giant.

Swiss diplomats have worked relentlessly to get the country's best-known bank off the hook. The SonntagsBlick newspaper said the lights in the office of Justice Minister Eveline Widmer-Schlumpf were burning until 3 a.m. last week. Berne also held an emergency cabinet meeting on Monday.