Economic ties between the US and Switzerland have grown but the overall bilateral relationship has not improved in the past two years, the Swiss-American Chamber of Commerce said, according to the AFP news service.

US lawsuits and regulatory problems for UBS – the Alpine state’s biggest bank - and a Swiss refusal to negotiate a free trade agreement were among key elements weighing on the relationship, the chamber said.

"It will be crucial to put maximum effort in building early bridges with the new US administration [to take office next year] and make sure that Switzerland retains its long-standing role as a privileged partner," warned the 2,500-member business group.

The US is Switzerland's second largest export market, worth a record SFr18.4 billion ($16.75 billion) in 2007 while US exports to Switzerland rose 13 per cent to a record SFr9.4 billion.

The US is also the single largest foreign investor in the country, with $100 billion committed as of last year while Swiss investment there came to $163 billion.

Despite the healthy economic relationship, the chamber warned that there were uncertainties ahead.

"Looking ahead, several crucial question marks threaten the positive development of the Swiss-American business relationship," it said, citing the US economic slowdown and the November presidential elections.

Against this backdrop, it warned that in "the bilateral relationship between Switzerland and the US, the situation has not improved over the last two years."

"Finally, the current discussion on Swiss banking secrecy (rules) and the troubles of a large Swiss bank in the US do not help to improve the relationship," the chamber said, referring to UBS.

UBS has come under pressure in the US for allegedly facilitating tax evasion by wealthy US citizens, prompting it to drop offshore banking operations in the country.