Bern  - Switzerland will reopen negotiations with the US on their bilateral taxation agreement, the Swiss Federal Council confirmed Wednesday - but warned any new treaty may be subject to a referendum.

The first meet is set to take place on April 28 in Bern.

The move follows Switzerland's announcement last month that it would relax its notorious banking secrecy laws and adopt more international standards on taxation and transparency in response to an international crackdown against so-called tax havens.

UBS, Switzerland's largest bank and the world's largest wealth manager, has been entangled in legal cases in the US since the middle of last year.

The bank admitted some of its employees committed wrongdoings in helping US citizens commit tax fraud. It agreed in February to pay a hefty fine of 780 million dollars and handed over data on some 300 clients accused of fraud, in what was seen as a major crack in the firewall of banking secrecy.

The US was still seeking data on thousands more clients.

Last month, the first UBS client was arrested on tax-related charges in Florida.

UBS has also ordered some of its wealth managers not to travel abroad until further notice, out of fears of legal proceedings.

Some Swiss commentators and politicians have voiced concern that their country and some other nations with banking secrecy were feeling the brunt of the crackdown, while regions under the protection of larger economic powers, like the US, Britain and China, were not being subjected to the same scrutiny.

Bankers have also expressed worries that relaxing the banking secrecy laws would cut into the country's financial sector, weakening a major part of the economy.

The issue of tax havens was featured on the agenda and in the final statement at the G20 summit in London last week.

Switzerland, along with other countries, was placed on a "grey list" of countries who have pledged to change their tax codes to better comply with international standards.

The bilateral treaties may be subjected to Switzerland's direct democracy, which asks citizens to vote on individual issues in referendums.

The right-wing Swiss People's Party has said it would oppose treaties which lead to a degradation of banking secrecy.

In the most likely scenario, only the first renegotiated bilateral would be subjected to a referendum, while ones with subsequent countries would only face a public vote if they entailed significant changes. (dpa)