"Without immediate action by Congress, American could slip into a financial panic and a distressing scenario would unfold," Bush said in a 12-minute prime-time address from the White House East Room that he hoped would help rescue his tough-sell bailout package.
Bush explicitly endorsed several of the changes that have been demanded in recent days from the right and left. But he warned that he would draw the line at regulations he determined would hamper economic growth.
"It should be enacted as soon as possible," the president said.
The bailout, which the Bush administration asked Congress last weekend to approve before it adjourns, is meeting with deep skepticism, especially from conservatives in Bush's own party who are revolting at the high price tag and unprecedented private-sector intervention. Though there is general agreement that something must be done to address the spiraling economic problems, the timing and even the size of the package remained in doubt and the administration has been forced to accept changes almost daily.
Seeking to explain himself to conservatives, Bush stressed he was reluctant to put taxpayer money on the line to help businesses that had made bad decisions and that the rescue is not aimed at saving individual companies. He tried to address some of the major complaints from Democrats by promising that CEOs of failed companies won't be rewarded.
"With the situation becoming more precarious by the day, I faced a choice: to step in with dramatic government action or to stand back and allow the irresponsible actions by some to undermine the financial security of all," Bush said.
Intensive, personal wheeling and dealing is not usually Bush's style as president, unlike some predecessors. He does not often call or meet with individual lawmakers to push a legislative priority.
But with the nation facing the biggest financial meltdown in decades, Bush took the unusual step of calling Democrat Obama personally about the meeting, said presidential spokeswoman Dana Perino. White House aides extended the invitations to Republican McCain and to GOP and Democratic leaders from Capitol Hill.
Obama spokesman Bill Burton said the senator would attend and "will continue to work in a bipartisan spirit and do whatever is necessary to come up with a final solution." Senior McCain advisers said McCain will attend, too. The plans of the other invitees were unknown, and the exact details of the meeting, which Perino said was aimed at making fast progress to stem the biggest financial meltdown in decades, were still being set.
In another move welcome at the White House, Obama and McCain issued a joint statement urging lawmakers - in dire terms - to act.
"Now is a time to come together Democrats and Republicans in a spirit of cooperation for the sake of the American people," it said. "The plan that has been submitted to Congress by the Bush administration is flawed, but the effort to protect the American economy must not fail."
The two candidates - bitterly fighting each other for the White House but coming together over this issue - said the situation offers a chance for politicians to prove Washington's worth.
"This is a time to rise above politics for the good of the country. We cannot risk an economic catastrophe," they said.
However, the Oval Office rivals were not putting politics aside entirely. McCain asked Obama to agree to delay their first debate, scheduled for Friday, to deal with the meltdown. Obama said the debate should go ahead.