A former UBS private banker, Bradley Birkenfield, charged with helping U.S. clients evade millions in taxes is going to plead guilty in court next month, reports The Times Online, the web edition of the fabled London-based newspaper.

The former director in UBS’ Wealth Management division intends to plead guilty to a single charge of conspiring to defraud the United States, according to the report. The story goes on to say that UBS has warned many of its international banking set not to travel to the U.S. lest they wish to be detained for questioning by U.S. authorities. (To read the Times story, click here.)

“UBS is treating these investigations with the utmost seriousness and has committed substantial resources to cooperate with both investigations,” the firm says in a statement. “UBS intends to appropriately and responsibly address and correct any issues raised in the investigations.”

Still, one top producer at UBS says it’s making management very jittery. He says Wealth Management Americas chief, Marten Hoekstra, was already making the rounds at the various branches giving pep talks to calm nerves—this is just one more item to discuss. It’s an important one too, judging from what one potential client asked him. “‘Do I think my firm will be criminally indicted?’ is what this guy asked me. How’s that for taking air out of the room?” he advisor says.

He says management is extremely tense. “I’ve never seen senior level management so nervous,” he says. “They’re trying to tell us everything’s going to be okay, but they’re under enormous pressure and there’s really not much good they can talk about,” he says.