Oil prices rose to near $119 a barrel on Thureday in Asia on fears that Tropical Storm Gustav could strengthen on its way toward crude and natural gas rigs and refineries in the Gulf of Mexico.

Royal Dutch Shell PLC said it's evacuating some 300 workers from offshore Gulf rigs, while BP PLC was also removing personnel from the region that's home to about a quarter of US crude production and much of its natural gas.

Though it was too soon to know where the storm would hit, some models showed Gustav taking a path toward Louisiana and other Gulf states devastated by Hurricanes Katrina and Rita three years ago.

One weather research firm predicted as much as 80 percent of the Gulf's oil and gas production could be shut down as a precaution if Gustav enters the region as a major storm.

Light, sweet crude for October delivery was up 80 cents at $118.95 a barrel in electronic trading on the New York Mercantile Exchange by mid-day in Singapore. The contract rose $1.88 overnight to settle at $118.15 a barrel.

Louisiana Governor Bobby Jindal declared a state of emergency and activated the National Guard in advance of storm Gustav. Jindal said on Wednesday that 3,000 National Guard troops will be activated and deployed a day in advance of the storm's expected landfall. An additional 2,000 troops could be called up to duty.

Gustav formed Monday and roared ashore Haiti on Tuesday as a Category 1 hurricane. The storm triggered flooding and landslides that killed 23 people in the Caribbean. It weakened into a tropical storm and appeared headed for Cuba, though it is likely to grow stronger in the coming days by drawing energy from warm open water.