WASHINGTON – Gen. David Petraeus slumped at the witness table Tuesday while testifying at a Senate hearing, and a spokesman said the general was likely dehydrated and jet-lagged from his travels.

Petraeus, 57, revived after a few seconds and left the room under his own power. After about 20 minutes he returned to the hearing room, but Sen. Carl Levin, the panel chairman, decided to postpone the hearing.

“It appears he was maybe a little jet-lagged, dehydrated certainly,” said Petraeus’ spokesman, Col. Erik Gunhus.

President Barack Obama later called Petraeus from Air Force One as he returned from a two-day trip to the Gulf Coast.

“Sounds like he’s doing good, he sounded great,” White House spokesman Bill Burton told reporters traveling with the president. “Sounds like he was just a little dehydrated.”

Petraeus had finished telling Sen. John McCain that he believed the planned 2011 drawdown of U.S. troops in Afghanistan remains on track, and McCain was responding when the room fell silent and aides began crowding around the four-star general.

Petraeus, who oversees the wars in Iraq and Afghanistan as head of U.S. Central Command, briefly put his head on the table, then rose, appearing dazed.

He stood under his own power and was escorted from the room.

Petraeus was taken to another room, given something to eat and drink and was examined by a doctor, Gunhus said. Petraeus returned to the room briefly and told the senators he was “feeling a little bit lightheaded there.

“It wasn’t Sen. McCain’s question,” the general added.

Gunhus said Petraeus had not been ill recently, although he had just returned from a weeklong overseas trip. Gunhus said Petraeus would continue his day as planned.

Last year, Petraeus underwent radiation treatment for the early stages of prostate cancer. He later announced the treatment had been successful.