Hawai'i's gasoline cap is poised to rise sharply in mid-March because of an increase in Mainland prices.

Through Friday the wholesale price cap average that will take effect March 13 was up 13 cents to $2.02 a gallon for regular on O'ahu, according to Advertiser calculations. That price excludes taxes and a retail margin. The cap won't officially be set until Wednesday and could rise or fall before then depending on how prices in Los Angeles, New York and the Gulf Coast change on Monday and Tuesday.

Gasoline prices, which had been declining during the last month, are poised to rise because of a jump in crude oil prices and speculation that refinery maintenance will cut supplies heading into the Mainland's warm weather driving season. Oil prices have spiked after a failed attack on an oil processing facility in Saudi Arabia.

State lawmakers passed the controversial price caps in an attempt to link Hawai'i's high, but stable prices to more competitive Mainland markets. The law was championed by Democrats in response to years of consumer frustration with gas prices that seemed to be higher than Mainland prices and resistant to movements in the oil markets.

Lawmakers now are considering amending or possibly repealing the caps. Just which tactic they take could hinge on how Hawai'i's gasoline prices react during the session that ends in May.

Reach Sean Hao at shao@honoluluadvertiser.com.