Transport Minister Eamon Ryan has admitted plans to cut excise duty paid on petrol and diesel 'won't be enough'.
The Government announced the measure in response to the rising cost of fuel as a result of the Russian invasion of Ukraine.
The plan would see a 15c cut in the price of diesel, a 20c cut in the price of petrol and a 2c cut in the price of green diesel from midnight until the end of August.
Minister Ryan says the Government's gone as far as it can.
"I think we should be honest with the public and say 'No, it won't be enough'.
"We are in exceptional circumstances and the level of price increases, it isn't possible and it changes by the day.
"And it keeps changing, so I don't think you could ever do enough.
"But we did need to do something, and Government has done this today - along with the €500m package that we announced three weeks ago to help householders on their electricity bills, and a long with measures done in last October's budget.
"This is a crisis that has been slowly evolving in terms of higher energy prices, but which took off in the last two weeks because of the invasion of Ukraine.
"We just have to be clear and honest: we can't fully protect against all the consequences of that.
"But we went to the max of what we could do within European law, and doing it in a way that was designed to be quick".