The US government has obtained information on about 70 American UBS clients as part of an on-going investigation by its tax authorities into the use of foreign banking centres to evade tax, according to a report in the Washington Post.

The report, citing people familiar with the matter, claims that the Swiss turned over the information for use by the US Justice Department, after receiving a request from the US government. The names of an additional 30 Americans holding UBS accounts in Switzerland have also been handed over to the US criminal prosecution authorities by other parties, the report says.

The report said it was unclear whether they were sent to the US government by UBS, the Swiss government or a combination. The report’s source said disclosures were usually authorised by the Swiss government.

UBS has declined to comment on the report.