BP sparked anger today with profits of £6.75 billion - the equivalent of £37million a day.

Unions and motorists accused the oil giant of cashing in on surging energy prices amid calls for a windfall tax.

The company insisted that the 23 rise in half-yearly profits compared with the same period last year was a legitimate reward for its efforts. Shell is expected to post high profits later this week.

BP said it obtained the bulk of its earnings from exploration and oil production, rather than sales at the pumps where it makes less than 1p in profit on every litre of petrol it sells at its 1,300 UK filling stations.

But the explanation cut little ice with critics. Tony Woodley, joint leader of the union Unite, said: "While ordinary people struggle to make ends meet, BP's boardroom is wading through knee-deep profits.

"It is high time our government moved to stop the fuel corporates picking the pockets of the poor and needy.

"A windfall tax now would ensure the money was there to help the old and vulnerable through these tough times." Neil Greig, director of the Institute of Advanced Motorists Motoring Trust, added: "Many will find it hard to accept the continued huge profits being made."

Petrol prices have soared since the start of the year, rising from an average of 102.8p per litre at the start of January to 118.2p at the end of June - a rise of 15 per cent. Diesel prices leapt 22 per cent over the same period.

Pressure on BP over its fuel pump prices increased last week when several supermarkets announced cuts in their forecourt charges.

Sainsbury said it was cutting 5p a litre from the price paid by motorists buying at least £50 worth of fuel, while Asda, Morrison and Tesco have also announced cuts. BP says that the price of petrol at the 310 garages where it controls prices has gone down by 2p.

Wendy Nichols, 61, from Barnes, a magazine writer, said: "These profits are absolutely outrageous. It's really quite shocking. Perhaps we should start boycotting companies like BP. If we all boycotted the biggest petrol company it would force prices down."

Charlotte Harman, 45, a university lecturer from Hammersmith, added: "What do they do with their profits? It's much more expensive to fill my car now - £54 for a tank of diesel, compared with £45 a few months ago."

BP's profits are all the more striking because the company has faced a difficult year, suffering major problems with its Russian operations and controversy over a huge job-cutting programme in the UK.

Under chief executive Tony Hayward, BP is benefiting principally from the surging oil price which reached 144 dollars a barrel last month before slipping back in recent weeks. In response to calls for a windfall tax, the company said it paid £7.3 billion in taxes worldwide last year - of which £1.17 billion was in the UK.

• 

  Sex, lies and the Stasi

  On this day in 1989 the Berlin Wall was finally breached, ending the reign of East Germany’s feared security service. Here Anne McElvoy, who spent much of the Eighties in the city, recalls her encounters with the spooks

  ---

• 

  The geeky-girl solo artists descending on the music scene

  Kookiness is what sells music these days and these opinionated artists have it in spades, says Jasmine Gardner

  ---

Why Sam's in the clear over that M&S dress

At last the truth about the M&S spotted dress that Sam Cam wore to the Conservative Party Conference

All stories