OIL companies on both sides of the Atlantic will gush record profits this week, with America’s Exxon Mobil posting the world’s biggest-ever profit, and Shell setting a new record for British companies.

Exxon is tomorrow expected to unveil a profit of about $32 billion (£18 billion) for 2005, according to Thomson Financial. It will be the largest single profit in the history of corporate America.

It shatters last year’s previous record for a company of $25 billion, set by Texas-based Exxon, the world’s largest listed oil company, and easily trumps the benchmark $22.1 billion made by Ford in 1998.

On Thursday Shell will top record-setting results with an estimated profit of $23 billion for 2005. This is up nearly a third from 2004, when its profits were $17.6 billion, at the time the biggest by a British company.

BP is expected to continue the trend on February 7 by revealing full-year profits estimated at $21.7 billion. This contrasts with earnings of $16.4 billion in 2004.

Oil-company profits, driven by the surging price of oil and gas, have drawn criticism as the cost of petrol remains high and domestic-heating bills soar.

Gordon Brown increased taxes on oil companies in his pre-budget statement in November. The tax rise, which came into effect this month, has already caused Shell to scale back its plans for exploration in the North Sea.

The bumper profits enjoyed by big British companies have caused several political outcries in recent years, especially those posted by Vodafone and HSBC.

In November American oil firms were forced to justify their bulging third-quarter profits to Congress, where they tried to dissuade the US government from imposing a windfall tax on their gains. Exxon has long been a focal point for criticism, not least because the $34 billion in its coffers could pay for the construction of more than a dozen refineries.

Shell, the world’s third-largest oil firm by market value, is still living down a reserves scandal that shocked investors two years ago.

The revelation that its oil and gas reserves were overstated hit Shell’s shares hard and forced changes in the way it is run.

The Anglo-Dutch company will announce the details of the 2006 share buyback programme alongside its results. Shell paid dividends of $10 billion in 2005, up from $7.2 billion in 2004, and bought back shares worth $5 billion, compared with $1.7 billion in 2004.