Motorists and transport businesses are being warned to expect an end to a cut to the fuel tax as conflict flares up between Iran and the US.
The fuel excise was temporarily halved by the Albanese government, slashing 26 cents off a litre, in response to soaring global oil prices caused by the war in the Middle East.
The $2.5 billion measure is planned to run out at the end of June, as Transport Minister Catherine King indicated it would not be extended further.