Gasoline pump prices rose nearly a nickel a gallon nationwide to their highest levels since 1986 because of the Alaskan oil spill and other supply constraints, an industry analyst said.

Prices are likely to continue rising in coming weeks because of the supply pinch and the seasonal increase in driving, said Trilby Lundberg.The latest Lundberg Survey of 12,000 gas stations found overall prices rose an average 4.86 cents to $1.1544 per gallon from April 8 to April 21. That was the highest price since early 1986, Lundberg said.