The US National Hurricane Center said Igor, the fourth hurricane of the 2010 Atlantic season, had top sustained winds of 75 miles per hour (120 kph), a Category 1 hurricane on the five-step Saffir-Simpson scale.

At 11 p.m. EDT (0300 GMT), it was located about 1,275 miles (2,050 km) east of the Leeward Islands, and was moving westward at 17 miles per hour (28 kph), the center said.

"Additional strengthening is forecast and Igor could reach major hurricane strength by late Monday," it added.

A major hurricane is one with sustained winds between 111 and 130 mph (154-177 kph), reaching a Category 3 rating on the Saffir-Simpson scale of intensity.

Hurricane Igor was seen moving west for the next two or three days, after which it was expected to turn more to the northwest, forecasters at the center said.

Computer models projected it would stay in the Atlantic for the coming days and not enter the Gulf of Mexico, where US oil and gas operations are clustered.

The 2010 Atlantic hurricane season was predicted to be extremely active by most forecasters. Besides Igor, three hurricanes — Alex, Danielle and Earl — formed earlier in the season, the last two reaching Category 4 strength.

Several forecasters have said they expect the season to produce in all some five major hurricanes of Category 3 strength or stronger.