This put it on a collision course with Germany, France and the UK, among others, who have promised to cut budgets amid rising debt worries.

"The international community united as one spirit during the crisis," said South Korean President Lee Myung Bak. "But now there are doubts over whether such cooperation can be achieved since the global economy is entering a recovery phase, with each country growing at a different pace."

The expanded number of voices at the table after the G20 replaced the G7 as the leading body to manage the global economy may help explain the increased noise, said Michael Paulus, Managing Director of Asia Public Sector Group at Citigroup Inc. in Hong Kong.

"When you've got 20 members that are trying to agree on something, it is much harder when there were seven," he said.

Since the global recovery remains fragile, G20 leaders need to look beyond their own economies and stand firmly together against the uncertainties, said Ba Shusong, a senior economist at the Development Research Center of the State Council.

A strong boost

Although lacking in detail, it is hard to deny that the agreements in Seoul came as a needed boon for the world economy.

In the joint communiqué, the G20 countries recognized the vital role of small and medium-sized enterprises (SMEs) in employment and income generation. Canada, South Korea, the United States and the Inter-American Development Bank jointly committed $528 million to help SMEs through grants and co-financing.

In another move, the G20 aimed to support country-led green growth policies and facilitate energy efficiency and clean energy technologies. It also confirmed the shift of over 6 percent in IMF quota shares from advanced economies to emerging ones, and called for deeper reforms to shape a more legitimate, credible and effective IMF.

When G20 countries face the undue burden of adjustment, policy responses in emerging market economies with adequate reserves and increasingly overvalued flexible exchange rates may also include carefully designed macro-prudential measures, said the communiqué. Many economists believed this was a hint of allowing emerging economies to set up capital controls and stem the tide of capital inflows.

Another bright spot was a deep commitment to keeping markets open and liberalizing trade and investments.

"We will refrain from introducing and oppose protectionist trade actions in all forms and recognize the importance of a prompt conclusion of the Doha negotiations," said the communiqué.

Next year, 2011, is a critical window of opportunity, albeit narrow, to round things off, it added.

WTO members started the Doha round of global trade talks in 2001, with a mandate to help poor countries prosper through more trade. But the negotiations have long been stalled because of sharp disagreements over farm trade subsidies and industrial market access.

"The fear we should all have is a return to what happened in the 1930s—protectionism, trade barriers, currency wars, countries pursuing 'beggar my neighbor' policies—trying to do well for themselves but not caring about the rest of the world," said British Prime Minister David Cameron.

In a recent report, the WTO said G20 countries had continued to exercise restraint in imposing new restrictions since their last summit in Toronto at the end of June. New measures, increasing but at a slower rate, covered 0.3 percent of G20 imports and 0.2 percent of the total world imports, it said.

"Cohesion and cooperation defined the G20 during the crisis. This allowed decisive policy action to help avert a second Great Depression," said Dominique Strauss-Kahn, Managing Director of the IMF. "Now, the challenge is to secure the recovery and to create the growth and jobs that the world needs. We all recognize that much remains to be done but the Seoul Action Plan is a step in the right direction."