(Adds IMF quotes on yuan and bank levy)
By David Lawder and James Pomfret
BUSAN, South Korea, June 5 (Reuters) - The International Monetary Fund believes global growth will suffer if the Group of 20 rich and developing economies fail to coordinate efforts to rebalance global demand, IMF officials said on Saturday.
Coordinated policies to encourage savings and cut budget deficits in wealthy countries such as the United States and to spur domestic demand in developing economies like China could boost growth substantially.
Speaking at the end of a G20 summit for finance ministers and central bank governors in the Southern Korean port city of Busan, the IMF's managing director Dominique Strauss-Kahn said he was also "totally comfortable" with a final communique calling for troubled euro zone countries to accelerate fiscal consolidation.
"They have to consolidate strongly even if it has some bad effect on growth," he said, referring to Greece and other southern European countries saddled with huge debts.
"Some countries have to go back rapidly to normalcy. Some others may go on with letting the stimulus expire by its own."
An IMF report presented at the G20 meeting earlier estimates that coherent adoption of the adjustment policies could increase global growth by as much as 2.5 percent annually over a medium-term five year period.
Strauss-Kahn said 30 million extra jobs could be created with these policy moves.
Last September, the G20 leaders pledged to take steps to rebalance global growth to eliminate huge trade surpluses in Asia and a massive buildup of debt in wealthier countries. They asked the IMF to study effects of differing speeds of implementing such policies.
Strauss-Kahn said Europe's woes were a global problem and it was important that Asia, through its currencies, help with the vital global economic rebalancing.
"The IMF still believes the renminbi (yuan) is till substantially undervalued ... (but) even a revaluation of 20-25 percent doesn't solve all the imbalances and you have more to do, so it's only part of the problem and you still have other imbalances."
It found that if the wealthy countries cut deficits and increased savings without complementary actions by developing export-oriented economies to boost domestic demand, short term growth would suffer in both. The wealthy countries would see more growth in the longer term as a result of an improved fiscal footing, but developing countries would see lower growth in both the short term and long term.
The paper was one of three presented by the IMF to G20 meetings in Busan. In a final draft of its study of bank taxes to pay for bailouts, it recommended that financial institutions pay levies similar to insurance premiums.
These would be based on risk-weighted liabilities. "The more risk you create, the more you should pay," the official said.
The IMF favours collecting the levies before a financial crisis hits because this would spread costs of banking failures evenly -- to both survivors and failed institutions.
The bank tax recommendations, however, may fall on deaf ears, as there was little agreement at Busan on bank levies, with some countries steadfastly against them, and differing views on their methods. The final communique by the ministers made no reference bank levies.
"I won't say it's the end of this idea," said Strauss-Kahn, while conceding countries might end up doing different things.
The IMF's other briefing paper reaffirmed its global economic forecasts issued in April, which predicted global economic growth at 4.2 percent for 2010.
The IMF official said the financial turbulence emanating from Europe has "added to the realism of the downside risks that were already described in the World Economic Outlook."
(Additional reporting by David Milliken; Editing by Jonathan Thatcher)