US authorities Friday opened 7,000 square miles (18,000 square kilometers) of waters in the Gulf of Mexico to fishing, bringing to 96 percent of federal waters now deemed safe months after the world's biggest oil spill.

The National Oceanic and Atmospheric Administration said the newest area reopened was about 80 nautical miles south of the Florida panhandle.

It was the 10th reopening in federal waters since July, when BP engineers capped a ruptured well at the sea floor that spilled millions of barrels into the waters.

"This is another important area for fishermen who target tuna and mahi mahi," said Jane Lubchenco, under secretary of commerce for oceans and atmosphere and NOAA administrator.

"Our tests continue to reveal seafood from the reopened areas is safe to eat."

No oil or sheen has been documented in the area since July 19, officials said.

At its closest point, the area to be reopened is about 60 miles (100 kilometers) east of the Deepwater Horizon BP wellhead.

The remaining closed area now covers 9,444 square miles (some 24,000 square kilometers) or about four percent of the federal waters in the Gulf.

At one point as much as 37 percent of these waters had been closed to commercial and recreational fishing.

The Deepwater Horizon oil rig exploded on April 20, killing 11 workers. Two days later it sank to the bottom of the Gulf, setting off one of the largest and costliest environmental disasters of all time.

The leaking Macondo well was eventually capped in July and permanently sealed last month, but the full extent of the damage is still unclear.

Some 205 million gallons of oil flowed into the Gulf after the April 20 explosion aboard the BP-leased Deepwater Horizon oil rig, impacting the crucial fishing and tourism industries and destroying hundreds of miles of the region's fragile coastal ecosystems.