The government has been urged to scrap planned fuel duty rises amid fears that prices at the pumps could reach as high as 140p a litre by April.

Brian Madderson, chairman of the Retail Motor Industry Federation's petrol division, urged Chancellor George Osborne to "halt the relentless rise in fuel prices" .

In a letter to Mr Osborne, Mr Madderson said average petrol prices were already at 128p a litre with diesel close to its record-high of 133p a litre.

On diesel, Mr Madderson said: "We anticipate a new high within days and expect the price to reach 140p a litre from April 1."

He went on: "Our unequivocal recommendation is that the Government now abandon the fuel duty `escalator' principle as this is a legacy of your predecessors.

"We are mindful that the plan to increase duty yet again by 1p a litre in `real terms' from April 1 will add a further 4-5p a litre to the retail price at the pumps for all grades of fuel."

Mr Madderson said that by Easter average petrol prices could be as high as 136p a litre, with diesel at "an unthinkable" 140p.

He told Mr Osborne: "We lament the fact that neither you nor your ministers or officials have yet involved industry in any of its changes to taxation directly affecting road fuel pricing.

"However, we remain willing and available to discuss these serious issues at any time."