A final out-of-court settlement has not yet been been reached in a tax-evasion dispute pitting the U.S. government and against Swiss bank UBS AG , a Justice Department attorney said Friday.

"The parties are still talking," said Stuart Gibson, an attorney for the tax division of the Justice Department.

He asked Miami federal court judge Alan Gold, who is presiding over the case, to delay a teleconference on its status until later Friday morning and Gold agreed, setting a new call for 11:30 a.m. EDT.

The parties had been widely expected to announce a final settlement of the U.S. case seeking the identities of thousands of wealthy American clients suspected of using offshore accounts at the bank to conceal assets and evade U.S. taxes.

Gibson told Gold in a teleconference last Friday that the two sides had reached an agreement in principle and hoped to resolve remaining issues in the coming week.

It was not immediately clear what obstacles to a final deal still needed to be overcome but the call at 11:30 a.m. was expected to shed more light on the state of play in the case, which has threatened to harm relations between the United States and Switzerland.