New figures show that the cost of a litre of petrol or diesel has reached its highest level in 18 months.

AA's Ireland's latest monthly fuel prices survey show that a litre of petrol now costs 137.7 cent, up a cent on February prices. It also marks the sixth monthly increase in a row.

Diesel costs 127.1 cent a litre on average across the country, a month-on-month increase of 0.7 cent. 

The AA said that with the latest increase, fuel costs have now reached their highest level since August 2015, when the average cost of petrol and diesel stood at 143.6 cent and 128.8 cent a litre respectively.

It noted that the latest increase comes despite the price of a barrel of oil falling by $5 and said that tax remains one of the major driving forces behind the overall cost.

According to AA analysis, 86.52 cent of the total pump price for a litre of petrol and 73.67 cent of the total per litre cost of diesel consists of various taxes including VAT and Excise duty.

"While it's easy to say that the factors which cause these increases are outside of our control as a country this simply isn't the case," commented Conor Faughnan, AA Director of Consumer Affairs. 

"The majority of what we pay at the pump is made up of various taxes placed on petrol and diesel and the extent to which we tax fuel spend is something we have direct say over," he added.

Mr Faughnan said that during the worst years of the recession tax on petrol and diesel increased by 20 cent and 18 cent a litre respectively.

"The fact that these taxes have outlived the "emergency" actually acts as an anti-stimulus measure making it more difficult for people to commute to work every day," he added.