WARWICK, R.I. (AP) — Rhode Island regulators have approved an electric rate hike proposed by the National Grid that's expected to increase monthly electric bills by more than 10 percent.

The state Public Utilities Commission voted Tuesday to approve the rate increase from 6.3 cents a kilowatt hour to 9.5 cents for residential customers. It will take effect on Oct. 1 and last through March 31.

The National Grid has blamed the increase on high prices in the regional energy market. WPRI-TV reports a spokesman says he expects the higher prices to persist.

The utility estimates the average customer who uses 500 kilowatt hours a month would pay about $17 more.

Democratic Gov. Gina Raimondo says the rate increase will "create uncertainty for many Rhode Island families and seniors who live on fixed incomes."