Soaring gasoline prices on the prairies have pushed the national average to a five-year high, according to an online price monitoring firm.

Dan McTeague of says the national average price for regular gasoline was 136.0 cents per litre on Thursday, up from 105.2 cents on the same date last year and closing in on the previous high of 139.1 cents in June 2013.

In Saskatchewan, gas prices jumped 10 cents a litre overnight in Regina and Saskatoon, with the average price in Regina sitting at 129.4 cents a litre and 130.6 cents a litre in Saskatoon.

In Alberta, prices are sitting at an average of 138.2 cents per litre in Calgary and 136.2 cents a litre in Edmonton.

McTeague says the biggest cause of this week's surge in prices was "gas bar shenanigans," as retailers who hadn't passed on recent increases in wholesale prices decided to catch up all at once.

He doesn't expect the increases to stick, pointing out some stations in Edmonton are already retreating.