Washington- US President George W Bush greeted leaders from the world's 20 top economies on Saturday for an historic summit aimed at stabilizing the financial system and halting a global economic slide.

Bush, in a brief statement, said he was pleased with the early results after leaders held a working dinner Friday night, but again warned against nations restricting free markets and trade as a result of the financial crisis.

"I am pleased that we're discussing a way forward to make sure that such a crisis is unlikely to occur again. And I am pleased that the leaders reaffirmed the principled behind open markets and free trade," said Bush, as he welcomed leaders at Washington's National Building Museum.

According to a draft of the final declaration obtained by Deutsche Presse-Agentur dpa, world leaders were expected to sign an agreement that will close all gaps in the regulation of world finance markets.

Finance ministers have been given a deadline of March 31 to hammer out the specifics, followed by another summit of the G20 leaders at a later date. The next summit is most likely to be held in London, but a formal announcement was expected later Saturday. (dpa)