UBS, Switzerland's biggest bank, today posted a 19% rise in first-quarter net profit, helped by higher income from its investment bank amid a pickup in global market volatility.

A 23% jump in its investment bank's pre-tax earnings and a strong performance in its flagship wealth management business, helped the bank's first-quarter earnings of 1.51 billion francs ($1.6 billion) beat the average Reuters poll estimate of 1.37 billion francs. 

Bullish capital market developments helped the investment bank increase revenues from equities trades, and it netted more money from helping clients arrange deals, particularly in Asia. 

"We had an excellent start to 2018, with our results once again showing the power of our diversified business," chief executive Sergio Ermotti said in a statement. 

A surge in volatility kept traders busy and revenues rising during the first three months of 2018. 

Many investment banks took a hit from deals disappearing and firms backing away from planned market entries for fear of netting less than hoped. 

UBS, however, brought in more business during the quarter from advising corporate clients, as private transactions also helped counteract a drop in public offering revenues.

"Advisory revenues increased to 186 million francs from 166 million, reflecting higher merger and acquisition revenues against a global fee pool decline of 15 percent, and higher revenues from private transactions," the bank said in its quarterly report.

Its flagship wealth management business made 19 billion francs in new money thanks to strong performances in the US and Asia. 

Despite the earnings beat, UBS struck a cautious note for the coming quarter, saying it saw geopolitical tensions and rising protectionism as threats to investor confidence.