BNP Paribas on Wednesday posted a forecast-beating 5.2 percent rise in net profit for the first quarter.
Net profit came in at 1.668 billion euros ($2.302 billion) in the first quarter of this year, beating analysts' expectations of 1.39 billion euros. It warned of larger than expected litigation fees however.
BNP took a $1.1 billion litigation provision in February related to a review of U.S. dollar payments involving parties subject to U.S. economic sanctions.
The U.S. authorities have already imposed big fines on other banks for breaching sanctions against U.S. dollar payments involving Iran and other countries.
The French lender said a "high degree" of uncertainty existed surrounding the fines that U.S. authorities could impose on the bank.
"There is the possibility that the amount of the fines could be far in excess of the amount of the provision," the bank said in a statement, following discussions that took place in the first quarter of this year concerning U.S. dollar payments.
In the firm's investment banking arm, fixed income revenues were down 21.7 percent due to weak activity in the rates and foreign exchange business.
The Paris based bank said domestic markets grew by 5 percent compared to the same period last year, with growth in France, Belgium and Germany.
The group said its balance sheet was "rock-solid" and its Basel common equity Tier 1 ratio 3 was at 10.6 percent, with 264 billion euros available in immediate liquidity reserves.