The leaders said that they were determined to work together to achieve "needed reforms" in the world's financial systems.
US President George W Bush said that finance ministers would now work on detailed reform proposals, and then report back.
Mr Bush's successor in the White House, Barack Obama, said in a statement that he was ready to work "together on these challenges" with the G20 when he takes office in January.
"The president-elect believes that the G20 summit... is an important opportunity to seek a coordinated response to the global financial crisis," said a statement issued in his name.