Word about the Category 5 development reached FEMA shortly before Paulison briefed reporters.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

WASHINGTON (AP)—President Bush, confronted with the prospect of a second monster hurricane striking the still-battered Gulf Coast, checked in with governors and federal officials Saturday to make sure Washington was doing all it can.

The president called state leaders in Louisiana, Mississippi, Alabama and Texas in the early morning from the White House before heading out for a 90-minute bike ride, spokesman Scott Stanzel said. Those states are in the potential path of Hurricane Gustav, which has been cutting a deadly route through the Caribbean and swelled into a fearsome Category 4 hurricane Saturday.

It was expected to cross Cuba's cigar country before moving into the Gulf of Mexico, where it could gather even more strength. Gustav could reach the U.S. by early Tuesday, anywhere from the Florida Panhandle to Texas. But just three years after Hurricane Katrina drowned New Orleans, a calamity from which the city still is not nearly recovered, it appears very likely to get slammed again, by at least tropical-storm-force winds if not worse.

Bush also received regular updates from aides about the storm's path and the government's preparations.

The president asked each governor what was needed from the federal government, Stanzel said. Bush praised them for mobilizing their states so effectively to get ready.

"He told each of the governors that federal officials were monitoring Hurricane Gustav very closely," Stanzel said. "President Bush pledged the full support of the federal government."

The Bush White House was badly burned by its fumbling response after Katrina struck the Gulf Coast in August 2005. Bush's image as a strong leader has never entirely rebounded, even though he has labored to improve on the Katrina performance since by displaying his concern and effectiveness in times of disaster since.

On Friday, Bush pre-emptively declared states of emergency for Louisiana and Texas. Such a move is rarely taken before a disaster hits. The declaration clears the way for federal aid to supplement state and local efforts and formalizes coordination. The administration did the same thing before Katrina struck.

Homeland Security Secretary Michael Chertoff and Federal Emergency Management Agency chief David Paulison were in the region monitoring developments. Equipment was put in position and safe shelters readied, with cots, blankets and hygiene kits en route.

The White House kept a close eye on developments to see whether Bush might need to change his plans to travel to St. Paul, Minn., on Monday to address the Republican National Convention. White House press secretary Dana Perino said such decisions probably would not be made until the last minute.

One of the reasons Bush was so criticized after Katrina was that he stuck to a schedule that took him from his ranch in Texas on a two-day trip to Arizona and California. There, he promoted a Medicare proposal while making just scant references to Katrina even as it slammed the Gulf Coast. Bush even happily strummed a guitar backstage at one event. He did not return to Washington until two days after the storm and did not visit the region until five days after.

This sort of dilemma also could have implications for the GOP convention as a whole. If the storm's landfall is serious, Republican John McCain said he probably would rethink allowing the four-day political gathering to continue.

"It just wouldn't be appropriate to have a festive occasion while a near tragedy or a terrible challenge is presented in the form of a natural disaster," McCain said in an interview taped Saturday with "Fox News Sunday." "So we're monitoring it from day to day and I'm saying a few prayers too."