London-based Barclays bank says it may cut costs if "challenging" economic conditions persists throughout the year.

The warning came as the bank said Thursday that revenue dropped 2% to 5.25 billion pounds ($6.77 billion) in the first quarter of 2019. Pre-tax profit from Barclays' corporate and investment banking business fell 30%.

Barclays says the "income environment in the quarter was challenging" and it will reduce spending "if this were to persist for the remainder of the year."

The bank says it has already cut bonus and compensation payouts across the corporate and investment bank to reflect the division's poor performance.

Barclays reported quarterly net income of 1.04 billion pounds, compared with a year-earlier loss of 764 million pounds, when the bank set aside 2 billion pounds to cover misconduct.