Agreement by leaders of the world's top economies to modernize financial regulation and cooperate more fully will help keep the global financial meltdown from getting worse, he told reporters at a news conference after the summit.

"One of the key achievements was to establish certain principles and take certain actions for adapting our financial systems to the realities of the 21st century," said the U.S. president.

Leaders from G20 agreed Saturday to undertake a coordinated action to tackle the ongoing global financial crisis and explore measures to prevent similar crisis in the future.

"We are determined to enhance our cooperation and work together to restore global growth and achieve needed reforms in the world's financial system," said the leaders in a declaration issued at theG20 summit.

"Leaders at this summit agreed on some other matters of importance. One is to reject protectionism and refrain from erecting new trade barriers. This is a very important part of this summit," said Bush.

"All this is an important first step, in other words, this is a beginning of a series of meetings," he added.

Described himself as free-market man, Bush also reiterated his free-market principle at the conference, saying "whatever we do, whatever reforms are recommended, we need to be guided by this simple fact: that the best way to solve our problems and solve the people's problems is for there to be economic growth. And the surest path to that growth is free-market capitalism."

Declaring he is retiring, Bush told reporter that President-elect Barack Obama's transition team has been fully briefed on what we intended to do here at this meeting.

The G20 leaders agreed to meet again by April 30, 2009, to review the implementation of the principles and decisions agreed at the Washington summit.