AUGUSTA – A strike by refinery workers in Venezuela and uncertainty about war with Iraq are among the factors this week that combined to cause the average price of home heating oil in Maine to jump 6 cents from last week.

This week’s average of $1.28 a gallon is 18 cents higher that one year ago, the State Planning Office reported Tuesday.

Prices ranged from a low of $1.19 a gallon in southwestern Maine to a high of $1.35 a gallon found in some central areas of the state. Kerosene prices increased 5 cents to $1.51 a gallon, and propane also was up a nickel to $1.57.

Venezuela supplies 14 percent of the crude oil supply to the United States. The South American country also supplies more than half of the crude oil supply for a refinery on the Virgin Islands that supplies gasoline, heating oil and kerosene to areas along the East Coast.

Colder than normal weather in parts of the country and mixed signals from the Organization of Petroleum Exporting Countries on quotas and production also have combined to help push prices nationally to more than $30 a barrel, an increase of about $5 a barrel since mid-November.