BP posted a 26 per cent surge in fourth-quarter replacement cost profit to $4.432 billion today thanks to high oil prices.
The world's second-largest oil firm said the replacement cost profit, which excludes changes in inventory values, included a $553 million charge for non-operating items, mainly due to a notional, non-cash loss on North Sea gas contracts.
Excluding such one-offs, BP's underlying profit was $4.985 billion, versus $4.765 billion for the last quarter of 2004.
But weaker-than-expected results in its refining and gas and power units meant it undershot forecasts. BP shares fell 2.3 per cent in pre-market trade.
Analysts had forecast of $5.75 billion for BP's fourth quarter replacement cost profit excluding exceptional items.
The company said the divergence was likely related to an unexpected $454 million non-cash charge BP was forced to take in its refining business under new accounting rules.
On top of proven reserves, BP also added nearly two billion new barrels to its non-proven resource base last year, taking it to a total of 41 billion barrels, of which the company expects to convert some 11 billion barrels into proven reserves by 2010.
BP said that assuming an oil price of $40 a barrel, output this year would be between 4.1 million and 4.2 million barrels a day.