Switzerland's bank secrecy remains secure, but the government wants to improve international cooperation on tax offenses, the finance ministry said on Friday.

The Swiss government has come under fire after allowing major bank UBS to disclose the identity of about 300 of its U.S. clients to avert criminal charges that Swiss regulators said would have put its existence at risk and hurt the economy.

Banking secrecy remains ensured, the Swiss finance ministry said in a statement. The government wants to improve the cooperation with other countries in the field of tax offenses, however.

Swiss banks are forbidden by law to divulge information on clients unless it is suspected that a Swiss criminal law has been broken. Under Swiss law, tax fraud is a criminal offense, but tax evasion is not, although it can result in financial penalties.

Switzerland is the world's biggest offshore financial centre, managing nearly one-third of an estimated $7 trillion in offshore wealth. Bankers have warned that the financial sector would shrink by as much as half without bank secrecy.

France and Germany have upped the pressure, proposing new steps against non-cooperative tax centres and calling for a revised set of criteria to determine whether Switzerland should be added to the list. (Reporting by Katie Reid; Editing by Victoria Main)