The company also announced Tuesday that it intends to sell its stakes in several assets in the Gulf of Mexico which it regards as non-strategic.
BP suffered huge damage to its reputation following the catastrophic blowout of the Macondo well on April 20, 2010, which triggered an explosion that killed 11 rig workers and leaked more than 200 million gallons of oil into the Gulf.
For the three months ending March 31, BP said its net profit was $5.9 billion compared to $7.3 billion a year earlier.
Replacement cost profit, a closely watched industry measure, was down 12 per cent at $4.9 billion from $5.6 billion a year earlier. The big difference came in the downstream category, where underlying replacement cost profit fell 58 per cent to $924 million compared to $2.2 billion a year earlier.
Within downstream, profits in the fuels business was down 63 per cent at $487 million, because of a much weaker performance from the supply and trading division, weaker demand, and the temporary shutdown of the Cherry Point refinery in the U.S. state of Washington following a fire in February.
Underlying replacement cost profit, excluding non-operating items and fair value accounting effects, was $4.8 billion, below the market consensus of $5.1 billion.
BP shares were down 2.1 per cent at 435.5 pence in early trading.
Despite a downbeat quarter, CEO Bob Dudley said the company had made a good start on its strategic priorities.
"During the quarter we gained access to significant new deep water and U.S. shale exploration acreage, our ongoing divestment program has reached $23 billion, and we have five deep water rigs at work in the Gulf of Mexico," Dudley said. "This operational progress will underpin the financial momentum we expect to come through as we move into 2013 and 2014."
BP said it was putting its stakes in several Gulf of Mexico assets up for sale, including the Marlin, Horn Mountain, Holstein, Ram Powell and Diana Hoover fields.
The company expects to have eight rigs working in the Gulf by the end of the year.
During the quarter, the company also reached agreements to resolve the majority of private economic loss and medical claims stemming from the Macondo leak.
"In all, despite legal uncertainty in relation to the Gulf of Mexico, the world's addiction to oil and a bargain valuation continue to underlie favourable long-term sentiment," said Keith Bowman, analyst at Hargreaves Lansdown Stockbrokers.