Profits at oil giant BP have plunged 44% to 720 million US dollars (£549 million) in the second quarter.
The slump in underlying replacement cost profit, the benchmark industry measure, comes as the sector battles with low oil prices.
BP boss Bob Dudley said: "Compared with a year earlier, the underlying second-quarter result was impacted by lower oil and gas prices and significantly lower refining margins, but this was partly offset by the benefit of lower cash costs throughout the group as well as lower exploration write-offs.
"We are delivering significant improvements to the business that will stick at any oil price. We are now well down the path of transforming our business to compete, whatever the future holds. We now see a much stronger outlook for BP and are focused on growth, both for this decade and beyond."
BP also booked a 2.8 billion US dollars (£2.1 billion) charge linked to costs associated with the Deepwater Horizon oil spill.
The total cost of the 2010 disaster in the Gulf of Mexico now stands at around 61.6 billion US dollars (£46.9 billion), with BP saying it has drawn a line under the payouts.
The group has also been slashing costs and axing jobs, cutting around 10% of its workforce to offset tough trading.
Oil prices fell to a three-month low on Monday amid concerns of a global oversupply of crude and natural gas. Brent crude fell 2.1% to 44.75 US dollars.
Brian Gilvary, BP's chief financial officer, said: "We continue to reset our capital and cost base and are moving steadily towards our aim of rebalancing organic sources and uses of cash by 2017 in a 50-55 US dollars per barrel oil price range."
On a non-underlying basis, losses for the second quarter narrowed to 2.2 billion US dollars (£1.7 billion) from 6.2 billion US dollars (£4.7 billion) in the same quarter last year. For the first half of the year, underlying profits came in at 1.2 billion US dollars (£914 million) compared with 3.8 billion US dollars (£2.9 billion) last year.