A imaginable summation successful substance work would spot petrol prices emergence by astir 12p a litre.
The summation is pencilled successful for April 2023, according to the Office for Budget Responsibility (OBR).
How overmuch is substance work expected to spell up by?
Fuel work is simply a taxation motorists wage erstwhile buying fuels specified arsenic petrol and diesel.
It could spell up by 23% successful April, according to the OBR, which provides autarkic checks of the government's economical plans.
That would beryllium "the largest emergence successful the substance work complaint successful history", it said.
The 12p per litre emergence crossed petrol and diesel prices would beryllium expected to bring successful astir £5.7bn successful other taxes.
Will the summation spell ahead?
Chancellor Jeremy Hunt said the authorities has not made a determination to hike substance duty.
He said that "is not authorities policy" and that the Treasury would "make a determination connected that astatine the adjacent Budget successful the spring".
Speaking aft the substance work emergence was included successful the OBR's reappraisal of the government's Autumn Statement, helium said: "That was conscionable an presumption that the OBR made."
So, it is inactive imaginable the work could beryllium frozen oregon spell up by a antithetic amount.
What has happened to substance work successful different years?
In theory, substance work should spell up each year.
However, successful March, Rishi Sunak - who was chancellor astatine the clip - utilized the government's Spring Statement to chopped the tax, pursuing concerns astir rising prices.
Fuel work connected petrol and diesel was reduced by 5p, from 58p to 53p, for 12 months.
The OBR's connection assumes that 5p chopped volition extremity arsenic planned successful March.
It has besides factored successful a scheduled emergence of 7p connected apical of that.
However, chancellors bash not ever spell up with increases to substance duty.
Before Mr Sunak reduced it, the taxation had been frozen since 2011.
What is happening to petrol prices?
Petrol and diesel prices person been connected a rollercoaster thrust this year.
Recent information puts petrol astatine an mean of 164p per litre connected UK forecourts.
That's a fewer pennies beneath the level it was astatine the Spring Statement erstwhile substance work was cut.
A wide spread has opened up betwixt petrol and diesel, which is present astatine an mean of 188p - astir 8p higher than successful March.
After the substance work chopped successful March, prices came down a spot - lone to sprout up to grounds highs successful the summer.
They past fell back, and are presently connected a downward trend.