Gustav is forcing Bush to change his convention plans.

(CNN) – President Bush is unlikely to be attending the Republican National Convention as planned because of Hurricane Gustav, the White House said Sunday.

The president had been scheduled to address delegates in St. Paul Monday night.

"Due to the hurricane, the president is unlikely to travel to Minnesota on Monday,” White House Spokeswoman Dana Perino said. “We are working on alternate preparations and we'll provide details as soon as possible.”

In a conference call with reporters Saturday, Perino said the White House was making contingency plans for the president's travel schedule before and after the hurricane, given what she described as one of the largest and strongest storms to hit America since modern record-keeping began.

Officials had already developed an alternate scenario for Bush’s speech as the storm’s intensity grew, telling CNN Saturday that if the president was not on hand at the convention site, first lady Laura Bush would give a longer speech than planned.

Under this scenario, the president himself would then speak via satellite from the White House or a location affected by the storm. The White House said then that a final logistical decision would likely not be made until Sunday evening, or perhaps Monday.