BRAZILIAN President Luiz Inacio Lula da Silva signed a decree and a provisional measure on Wednesday aimed at lowering fuel prices, weeks ahead of the presidential election and as the United States-Iran war drives up the cost of filling car tanks.

The cost of fuel is a particularly sensitive issue for voters, who will decide in October whether to grant Lula a fourth, non-consecutive term, or elect Senator Flavio Bolsonaro, a son of former far-right President Jair Bolsonaro.

Brent crude, the international standard, surged above the $100 (£74) threshold on Wednesday for the first time since July, after attacks on oil facilities and ships in the Middle East threatened to further strain an already weakened supply chain.

“We’re not going to allow this irresponsible war to hit your pocket,” said Lula as he signed the measures, which extend policies to control fuel prices introduced at the beginning of the US-Iran war.

The measures announced on Wednesday include tax cuts on the import and sale of ethanol, gasoline (petrol) and gasoline blends (excluding aviation gasoline), effective for 30 days from September 10 to October 9. 

Crude oil prices shot up shortly after Israel and the US began their illegal and unprovoked war with Iran in late February, largely because the fighting halted most shipping through the Strait of Hormuz.