MORE Swiss banks that helped wealthy Americans evade taxes will soon strike agreements with the US Department of Justice to avoid prosecution, an official overseeing the US government programme said.

"I would stay tuned," Acting Assistant Attorney General Caroline Ciraolo of the Department's Tax Division said on Tuesday, adding that a number of non-prosecution agreements will be signed in the "very near future".

Last week, Swiss bank BSI SA became the first bank to reach a resolution under a voluntary disclosure programme for tax-related offences run by the Justice Department. BSI agreed to pay a US$211 million penalty after admitting it had assisted thousands of US clients in opening accounts in Switzerland and hiding assets from tax authorities.