WASHINGTON. — Vast swaths of U.S. Pacific Ocean waters could be protected as marine sanctuaries or monuments, the White House said on Monday, drawing praise from environmental groups.

President George W. Bush started the process by directing the U.S. secretaries of the Interior, Defense and Commerce departments to assess whether certain locations in the Pacific should be designated as marine protected areas, White House spokesman Tony Fratto said.

The areas being considered for protection in the new plan are a group of islands and atolls in the remote central Pacific, including the Rose Atoll near American Samoa, and some of the waters around the Northern Mariana Islands in the western Pacific.

The move comes a month after Bush in a symbolic move lifted a White House ban on offshore drilling closer to home as gas prices soared. Environmental groups said expanded offshore drilling, which would still require congressional approval, would not cut gas costs and could hurt wildlife.

If all the new places mentioned by Bush were protected, the territory would total more than 891,000 square miles (2.308 million sq km), an area larger than Texas and Alaska combined.

"These areas are host to some of the world’s most biodiverse coral reefs and habitat and some of the most interesting and compelling geological formations in all of our oceans," Fratto said, speaking from Crawford, Texas.

Some of these areas are also of military and strategic importance, and Bush advised his cabinet secretaries that their recommendations should not limit military activities and should be consistent with freedom of navigation and international law.

Bush said any recommendations should take into account cultural, environmental, economic and "multiple use" implications, including whether to keep access to recreational and commercial fishing, energy and mineral resources and scientific study.

Bush established a national monument in the northwestern Hawaiian Islands in 2006, creating the largest marine protected area in the world. Monday’s announcement sets a process in motion that could result in more such protected ocean areas by the end of Bush’s presidency in January.

Joshua Reichert of the Pew Environment Group called the announcement "a hopeful sign for ocean conservation" but said designation as a marine sanctuary or monument could still permit commercial fishing and deep sea mining.

"However, if the president establishes these new sites as no-take reserves, where no extractive activity is allowed, it would be one of the most significant environmental achievements of any U.S. president," Reichert said in a statement.

"The president is on the cusp of conserving more territory than any leader has ever done. That’s an amazing legacy to leave the nation," said Fred Krupp, president of Environmental Defense Fund.