Fuel duty rose by 2p a litre today, taking the cost of diesel and petrol at the pump to the verge of £1 a litre.

The rise, announced by Gordon Brown in this year's budget, took the average price of a litre of unleaded petrol to 97.8p, with diesel averaging 99.8p.

Prices are likely to rise further, the AA said, with a 2p a litre rise due in April and another increase of 1.84p in April 2009 under the budget announcement earlier this year.

The AA said average prices in September last year were 88.07p a litre for petrol and 93.39p for diesel. The motoring group said that from today the average UK petrol driver would pay an extra £4.84 to fill the tank than a year ago.

Stephen Joseph, executive director for the Campaign for Better Transport (formerly Transport 2000), called for the extra duty revenues to be spent on public transport and other measures to give people "real travel choices".

"Since 1997, the real cost of motoring has fallen while the cost of using public transport has risen. We welcome this rise in fuel duty if it is used to help level the playing field among transport options," he said.

The Petrol Retailers Association director, Ray Holloway, who had asked for a deferment of the increase, said the latest rise would put "undue financial strain on motorists and petrol retailers alike".

He said the number of filling stations was falling and it would "not take much to push more stations out of business".

The Road Haulage Association and the Freight Transport Association had also called on the Treasury to defer the rise.

Both groups pointed out that the 2p rise takes the fuel duty element within a litre of diesel in the UK to 50.35p compared with a European average of 22.7p a litre.

The 2p rise today would add costs of £870 a year to the fuel bill for a 44-tonne articulated lorry on average mileage.

A Treasury spokesman said: "In this March's budget the government announced fuel duty rates for the next three years, providing certainty for business, sending the right environmental signals in our fight against climate change, while continuing to fund vital public services.

"After these changes, by 2010 main fuel duty rates will be 11% lower in real terms than they were in 1999. The changes were made alongside reforms to vehicle excise duty that cut rates for less-polluting vehicles, and a number of measures to support hauliers, which they have welcomed."

Oil prices last month reached a record $80 (£39) a barrel.