HSBC Holdings has beaten forecasts with a 31% rise in quarterly profit, bolstered by a surge in income from its core Asian business.

It also saw lower costs due to the absence of legal and regulatory expenses borne the same time last year. 

Reining in costs has been one of the biggest challenges for HSBC chief executive John Flint with the bank last year missing its target of 'positive jaws' - which tracks whether the bank is growing revenues faster than costs. 

The bank said operating expenses dropped 12% in the March quarter, helped by one-off sales in its retail and commercial businesses and the non-recurrence of regulatory fines. 

HSBC booked $897m in legal and regulatory expenses in the first quarter of 2018 but did not have those and others such as currency translation costs in the current quarter. 

"We are proactively managing costs and investment in line with this more uncertain (global economic) outlook, and will continue to do so," Flint said in the bank's earnings statement today. 

HSBC warned in February that it may have to delay some investments this year as it missed 2018 profit forecasts due to slowing growth in its two home markets of China and Britain. 

Profit before tax at Europe's biggest lender by assets rose to $6.21 billion in the March quarter from $4.76 billion in the same quarter last year. 

The profit was above the $5.58 billion average of analysts' estimates compiled by the bank. 

The bank's core capital ratio, a key measure of financial strength, rose to 14.3% at the end of March from 14% at the end of 2018.

While HSBC has been boosting investments to raise its market share in businesses such as retail banking and wealth management, some of its other units, mainly investment banking, struggled with staff exits and slower revenue growth. 

The division, which advises clients on finance and mergers, has lost senior dealmakers and slipped down the rankings in merger advisory and equity capital markets amid internal questions over its strategic direction. 

The lender reshuffled its global banking division this week as former JPMorgan banker Greg Guyett put his stamp on the business, which has been under pressure in recent years. 

HSBC's investment banking business had a poor first quarter, in common with many of its US and European rivals that saw trading revenues fall as subdued markets kept clients from trading. 

The London-headquartered bank, which makes the bulk of its revenue in Asia, saw its stock trading business fare particularly poorly, with revenues falling 8% despite a helpful one-off provision release.

Reported pretax profit for the bank's Asia operations rose 5% during the first quarter to $5 billion, with the region accounting for 81% of the bank's overall profits. 

HSBC's regional pivot is centred around China's Pearl River Delta region with billions in investment commitments and plans to bolster its retail and wealth management business in the world's second-largest economy. 

The bank said it was making more investments in Asia to "support business growth". 

Flint said in June last year that HSBC would invest $15-$17 billion over three years in areas including technology and China, while keeping profitability and dividend targets unchanged. 

The bank said that the turnaround strategy for its business in the US, which has for years underperformed, was progressing, but that task remained its "most challenging strategic priority". 

Its North America operations posted a pretax profit of $379m in the first quarter compared to a loss of $596m last year, as the bank increased retail customer numbers and capitalised on its international network, it said.