LONDON (Reuters) -Swiss bank UBS had an "okay-ish" start to the second quarter due partly to market volatility induced by U.S. tariffs, but if increased uncertainty persists it "will have an impact on our activity levels with our clients," UBS Chief Financial Officer Todd Tuckner told reporters on Wednesday.

Investment banks faced heightened market volatility at the beginning of April in response to the U.S. tariffs, which increased opportunities for traders to make profits, but also heightened the risks of losses as a result of wild and unexpected moves in certain products.

The Swiss franc, for example, rapidly appreciated against the U.S. dollar, surging roughly 7% in April, and is set for its biggest rise in over a decade.

A Swiss media outlet reported earlier this month that some UBS clients had lost money which was invested in currency derivatives products. UBS declined to comment on the report at that time.

When asked about the report of the possible currency product losses during a call with reporters on Wednesday after UBS published its results, Tucker said that "when there's volatility, there's going to be clients that generate gains from that volatility and clients to generate losses."

"We can't comment on and won't comment on the matter, but, you know, certainly in a volatile market, one can expect there will be swings, one would expect volatility in investment accounts," he added.