Updated from 11:40 a.m. EDT

Oil prices jumped for a fifth straight session Friday, moving abruptly on news that Saudi King Fahd has been hospitalized.

July crude was recently up 84 cents to $51.85 a barrel on Nymex, bringing to more than 6% its gain since assuming front-month status on Monday. Gasoline futures rose 2 cent to $1.47 a gallon.

Saudi Arabia, which produces about 12% of the world's oil supply, is reported to be in a state of emergency following the king's hospitalization in Riyadh. While any disruption in the Saudi government would trouble oil markets, the country has mostly been run by Crown Prince Abdullah since Fahd's stroke 10 years ago.

Earlier, prices inched higher in the aftermath of this week's Energy Department report showing an unexpected drawdown in U.S. crude inventories. Traders also eyed the Memorial Day weekend, one of the biggest driving periods of the year.

Geoff Sundstron at the American Automobile Association said the association expects a record 37.2 million Americans to travel 50 miles from their home during Memorial Day, 84% of those using their cars. That is 2.2% higher that last year.

Refineries have been stepping up their gasoline production ahead of the summer, with utilization last week rising to 94.6%. Still, gasoline inventories are at the higher end of the average for the year, according to the Energy Department's report, boosted by increased imports of over 10 million barrels a day.

The Senate Energy and Natural Resources Committee approved Thursday a bill that would allow the government to expand its strategic petroleum reserve by 300 million barrels to 1 billion barrels. The same bill eliminates the House's drilling initiative in the Alaska Wildlife Refuge.

"Both decisions are more of a political red-herring than practical," said Stephen Burns, bureau chief at Argus Research. He said that the government adds some 125,000 barrels a day to SPR, "which is only a drop in the sea" compared with the 20 million barrels of oil the U.S. uses on a daily basis. "The decision to add to SPR and the decision not to drill in Alaska are not going to affect oil markets anytime soon," Burns said.

The energy bill aims to save 1.1 trillion cubic feet of natural gas by 2020, cut peak electric demand by 2020, and reduce oil consumption by 1 million barrels a day by 2015.

In utility news,

Xcel Energy

(XEL) - Get Report

, which owns four electric and natural gas utilities, was raised to a buy from hold by Citygroup's Greg Gordon. He said the company's borrowing costs could fall in light of the decline in 10-year-bond yields. Shares rose 23 cents, or 1.27%, to $18.28.

Elsewhere,

American Electric Power

(AEP) - Get Report

said it will buy the Waterford Energy Center in Ohio from an affiliate of

PSEG

(PEG) - Get Report

TST Recommends

for $220 million.

Shares of

Canadian Natural Resources

(CNQ) - Get Report

rose more that 3% Friday ahead of its announced 2-for-1 stock split today. The integrated gas and oil company also said it priced a C$400 million principal amount of 4.95% unsecured notes due June 1, 2015 sold to investors in Canada.

The Amex Oil Index rose in late Friday trading by 1.2% as oil prices gained. Shares of major oil producers traded higher.

Exxon Mobil

(XOM) - Get Report

rose 0.70%;

Chevron

(CVX) - Get Report

gained 1.45%;

ConocoPhillips

(COP) - Get Report

increased 1.41%%;

Royal Dutch/Shell

( RD) gained 0.39%; and

BP

(BP) - Get Report

added 0.20%.