WASHINGTON — President-elect Barack Obama hailed a rare Oval Office gathering of all U.S. presidents as an extraordinary event today as the current occupant, President George W. Bush, reminded his predecessors and successor that the office "transcends the individual."

"I just want to thank the president for hosting us," the president-elect said, flanked by former President George H.W. Bush on one side and his son on the other.

Presidents Bill Clinton and Jimmy Carter, both smiling broadly, stood with them.

"All the gentlemen here understand both the pressures and possibilities of this office," Obama said. "For me to have the opportunity to get advice, good counsel and fellowship with these individuals is extraordinary."

In a swift photo opportunity, the current president wished Obama well before all five men headed to a private lunch that lasted about 90 minutes.

"I want to thank the president-elect for joining the ex-presidents for lunch," Bush said, even though he's not quite a member of that club yet.

"One message that I have and I think we all share is that we want you to succeed. Whether we're Democrat or Republican we care deeply about this country," Bush said. "All of us who have served in this office understand that the office itself transcends the individual."

He added: "We wish you all the very best, and so does the country."

Bush and Obama also met privately for roughly 30 minutes. That one-on-one meeting, coming just 13 days before Obama's inauguration, likely focused on grim current events, with war in the Gaza Strip and the economy in a recession.

It had been an entire generation since the nation last saw the tableau of every U.S. president together at the White House. The presidents have gathered at other locations over the years, most recently for the funeral of President Gerald Ford in Washington.

Obama suggested holding the gathering when he met Bush at the White House in November.

All parties seemed determined to keep details of what was discussed confidential.

Describing the lunch only in broad terms after it ended, Obama press secretary Robert Gibbs said: "The president and the former presidents had helpful advice on managing the office, as well as thoughts on the critical issues facing the country right now. The president-elect is anxious to stay in touch with all of them in the coming years."

Obama has sought to strike a balance as the power curve bends his way. Before taking office, he is publicly rallying Congress behind a massive economic stimulus plan. But he remains deferential to Bush on foreign affairs and will not comment on Israel's deadly conflict with Hamas on grounds that doing so would be dangerous for the United States.

"You can't have two administrations running foreign policy at the same time," Obama said at a news conference earlier in the day.

Vice President-elect Joe Biden also held a private meeting with former President Bush at the White House today.

Considering the bond they hold in history, U.S. presidents gets together infrequently, particularly at the White House. And when they are in the same room, it is usually for a milestone or somber moment — a funeral of a world leader, an opening of a presidential library, a commemoration of history.

Not this time.

"It's going to be an interesting lunch," Bush told an interviewer recently. When asked what the five men would talk about, Bush said: "I don't know. I'm sure (Obama's) going to ask us all questions, I would guess. If not, we'll just share war stories."

They have plenty of those, political and otherwise. Their paths to power have long been entwined.

Carter lost the presidency to Ronald Reagan, whose running mate was George H.W. Bush. Bush later won election but lost after one term to Clinton. Then Bush's son, the current president, defeated Clinton's vice president, Al Gore. And this year Obama won after long linking his opponent, John McCain, to Bush.

Those campaign rivalries tend to soften over time as presidents leave the White House and try to adopt the role of statesmen — although Carter, even as an ex-president, has had some critical public words for the current president's foreign policy.

All five men were to pose for a group photo in the Rose Garden, but a January rainstorm scrapped that plan. So the noontime photo opportunity — the media's only glimpse of them — was moved indoors to the Oval Office.

The presidents and Obama were having lunch in a private dining room off the Oval Office, where no one else was expected to join them.

"All of us would love to be flies on the wall and listening to that conversation," White House press secretary Dana Perino said.

The rare presidential joint appearance also offered Bush, who ends his two terms deeply unpopular, to again show he is rising above the fray.

The last White House event to draw the former presidents was a November 2000 celebration in honor of the White House's 200th anniversary. But one of the former presidents, Ronald Reagan, who was afflicted with Alzheimer's, was unable to attend.

All the presidents were last at the White House in 1981: Richard Nixon, Ford, Carter and Reagan, who was president then. The three former presidents were there before leaving as part of the U.S. delegation to the funeral of Egypt's Anwar Sadat, who had been assassinated.