Shell's first quarter profits have topped £2.7bn, an increase of 23% on the same period last year, helped by high gas and oil prices.
The results come as UK motorists face ever higher petrol prices on Britain's forecourts.
John Edmonds, general secretary of the GMB Union, said the profits hike showed the "greed" of the oil companies continued to "defy belief".
He said: "It is as if they are playing their own game of Who Wants to Be a Billionaire? at the expense of the motorist and the taxpayer.
"If they are not prepared to voluntarily curb their own lust for profit then the only solution is the introduction of a windfall tax."