<!--StartFragment--> A MIAMI judge has asked the US authorities if they would be prepared to shut down UBS operations in America entirely, if the Swiss bank does not agree to hand over details of 52,000 of its US clients accused of evading tax.<br /><br />In the latest chapter of an ongoing diplomatic row, Alan Gold &ndash; the judge set to kick off a court case on Monday to determine whether UBS should be forced to hand over the information&nbsp;&ndash;&nbsp;gave the government a deadline of Sunday to make clear what action it would take if UBS loses.<br /><br />In a court filing, Gold&nbsp;demanded to know if the US Justice Department is considering &ldquo;receivership and/or seizure of UBS&rsquo; assets within the United States&rdquo; if he finds against the investment bank.<br /><br />Switzerland and the US have been at loggerheads over the issue for months, with the Swiss government fearing that the case could damage the country&rsquo;s long-held tradition of bank secrecy.<br /><br />The rhetoric escalated earlier this week as the Swiss authorities threatened to confiscate the clients&rsquo; data if the court rules against UBS, to prevent it from complying with US demands for disclosure.<br /><br />UBS chief executive Oswald Gruebel yesterday circulated a memo to the bank&rsquo;s staff in which he said that &ldquo;honouring the IRS summons would require UBS to violate Swiss criminal law, and we simply cannot comply&rdquo;.<br /><br />If US authorities say they are prepared to freeze the bank&rsquo;s assets, they will be picking a fight with America&rsquo;s number one trader on all exchanges, threatening the livelihoods of some 27,000 employees in 381 cities.<br /><br />A source at UBS&nbsp;said last night that while &ldquo;there are lots of discussions going on on a government level&rdquo; the bank is focusing on the tax-evasion trial starting on Monday.<br /><br />&ldquo;Even if they said they would freeze our assets, then there are appeal processes. And such a threat could quicken any early settlement of the case,&rdquo; he said.<br /><br />Experts were saying last night there are now three likely outcomes, the most serious of which would be that courts demand the client details and UBS&rsquo;s US assets are frozen.<br /><br />Another might be UBS finding a way to reveal data of any tax evasion without revealing specific details of its US clients, enabling it to effectively charge the clients for any evasion itself and then pass on damages to the US.<br /><br />Or UBS might be able to negotiate a cash settlement with US authorities before the trial even begins, although sources said last night no such deal is imminent.<br /><br />UBS paid $780m (&pound;538m) in February to settle a separate but related criminal suit by US authorities, but the government is still pursuing a civil case in the hope of securing the details.<br /><br />Switzerland has already bowed to international pressure to establish reciprocal bank data-sharing arrangements with other countries, but the Swiss government has insisted it will only hand over details when it feels that the request is serious enough.<br /><br /><strong>TIMELINE: UBS TAX ROW<br /></strong><br /><strong>12 November 08<br /></strong>Raoul Weil, head of UBS&rsquo;s wealth management business, charged with helping thousands of wealthy Americans hide around $20bn of taxable assets in Swiss bank accounts.<br /><br /><strong>19 February 09<br /></strong>US authorities vow to continue a legal push for details of 52,000 clients of UBS, despite the bank paying a $780m (&pound;538m) fine to settle the criminal case.<br /><br /><strong>13 March 09<br /></strong>Switzerland agrees to make concessions on bank secrecy amid global crackdown on tax evasion.<br /><br /><strong>25 April 09<br /></strong>Switzerland asks the US to drop the civil case in return for a new tax accord.<br /><br /><strong>8 July 09<br /></strong>Switzerland threatens to&nbsp;confiscate the data, rather than allow UBS to hand it over. <!--EndFragment-->