Operating expenses rose to $9.4bn while revenue increased 6% year-on-year from $12.9bn to $13.7bn. Mr Flint said the 8 per cent rise in underlying quarterly costs reflected investments in its Chinese and United Kingdom retail banking operations, its Chinese securities joint venture and digital improvements across the group.
HSBC said that "in light of the growth opportunities that we now see", the $2 billion share repurchase programme is the only one expected for 2018.
Europe's biggest bank by assets, which earns most of its profits in Asia, has long struggled to hit its cost control targets.
The increased investment led to negative cost-to-income "jaws", being the difference between the rate of revenue growth and that of cost growth.
The banking giant also said it is planning a share buyback of up to $2 billion - the only one it said it expects to conduct this year.
Shares were down 1.4 per cent on the open.
Good morning. Profits at HSBC fell by an unexpected 4 per cent in the first three months of the year as the bank missed City forecasts.
The rising costs and subdued return on equity reported Friday underline the challenges. Net interest margin, banks' key difference between interest paid on deposits and that charged for loans, improved to 1.67 from 1.63 at the end of December and 1.64 a year ago. "The Hong Kong dollar is now at the weak end of the peg [to the USA dollar] so it's possible that we'll have a more sustained rise in Hibor rates soon", Mr Flint said.
The bank, which is now undergoing a major overhaul which has resulted in tens of thousands of people being made redundant in the last couple of years, reported a six per cent jump in revenues to $13.7bn.
Mr Flint, HSBC's former global head of retail banking, took over from Stuart Gulliver in February, hours after announcing a lacklustre performance for 2017.