Petrol forecourts have passed on less than half of the 5p fuel tax cut announced by the government.
Chancellor Rishi Sunak confirmed a 5p-a-litre cut to fuel duty as part of his Spring Statement last week.
The cut means drivers are paying 52.92p in tax for every litre of petrol and diesel from 6pm on March 23 until March next year.
But petrol prices have dropped by only 2.71p a litre and diesel by 1.59p, the AA told Sky News .
The motoring organisation said the average price for a litre of petrol was now 164.59p a litre and 178.72p for diesel.
The 5p tax cut means a 6p-per-litre price reduction when motorists fill up, because VAT is charged on top of fuel duty.
AA fuel price spokesman said: "The chancellor rode to the rescue of drivers on Wednesday and, even before the 6pm start of the fuel duty cut, drivers were reporting the price cut at some Asda forecourts.
"However, on Thursday, the average price of petrol showed that less than half (2.71p) of the fuel duty cut had been passed on to drivers."
Last week The Mirror reported that drivers were paying more to fill up their cars despite the government cutting fuel tax.
Forecourts in many areas were changing the same after the chancellor's tax cut came into effect - and some were even charging more.
The Mirror sent photographers to multiple petrol stations before and after the Chancellor's tax cut announcement to see how forecourts reacted.
An Esso forecourt in Brighton was charging 166.9p a litre for unleaded petrol last Thursday - the same as before the Chancellor's announcement on Wednesday.
But a litre of diesel at the same forecourt was 184.9p - up 5p in 24 hours.
But many petrol stations have passed on the cuts .
Asda, Sainsbury’s and BP have announced 6p a litre cuts , while Morrisons said it would lower prices by 5p per litre.
The Treasury said the fuel duty reduction would save motorists around £2.4billion in the next 12 months.
However, the fuel duty reduction represents just a “drop in the ocean”, according to the RAC motoring association.
Most Brits (72%) are 'very worried' about rising prices for fuel, according to market researchers Appinio.
1.3milion Brits including half a million children will be dragged below the poverty line despite Rishi Sunak‘s Spring Statement, devastating analysis says.
A typical working-age household will see their real income fall 4% next year - a loss of £1,100, the Resolution Foundation think tank said.
Absolute poverty - rather than relative poverty - is crucial because it is the measure Boris Johnson chooses to use.
In 2020 the PM controversially boasted poverty had fallen when relative poverty was up and absolute poverty was down .
It comes after the Budget watchdog said soaring inflation - expected to nudge 9% in a four-decade high - will inflict the biggest disposable income drop since records began in the 1950s .
The Foundation warned poorer Brits will be hit harder as the Tory Chancellor refused to raise benefits - which will rise at less than half inflation.
