By Jonathan Cable and Anooja Debnath
LONDON/SINGAPORE (Reuters) - The global economy is set to expand by a modest 3.3 percent this year as a still-smoldering euro zone debt crisis and a relatively slow U.S. recovery continue to leave Asia as the main driver of growth, Reuters polls showed on Thursday.
Asian economies, as well as Latin America, are expected to pick up the pace later this year, driven by monetary stimulus after a soft patch - a boost Western policymakers are increasingly unable to provide.
The U.S. economy has not taken off in the way many had hoped and the outlook there remains relatively subdued, although still much better than most of its Western peers.
"We think it is increasingly clear that the U.S. is on a fairly self-sustaining recovery and is reasonably - but not completely immune - from what is happening in the euro zone," said Andrew Kenningham, senior global economist at Capital Economics.
"In Europe, it's really a very different story. We expect recession this year, but we find it difficult to see why the euro zone would recover next year."
The polls of more than 700 economists across the world, taken in the past few days in the run up to this week's meeting of G20 finance ministers, predicted 3.3 percent global growth this year, unchanged from a poll taken three months ago.
That would mark a slowdown from the International Monetary Fund's 3.9 percent estimate for 2011 and is slightly less optimistic than their forecast for 3.5 percent growth this year.
But 2013 is expected to see a slightly better 3.8 percent, based on expectations that the euro zone crisis fades, the United States picks up steam and Asia finds its stride again.
A slowly improving U.S. job market and reasonably solid expansion at the start of the year brightened the outlook somewhat, and the world's biggest economy is now set to grow 2.3 percent this year and 2.4 percent next year.
U.S. recovery will help its southern neighbors and Brazil, after just 2.7 percent growth last year, will gain strength from near full employment, expanding by 3.2 percent in 2012 and by 4.3 percent in 2013.
In contrast, the euro zone is expected to shrink 0.4 percent this year and will linger in a mild recession until the third quarter - three months longer than forecast in March.
However, those figures mask a huge disparity between the region's stronger economies, such as Germany and France, and weaker ones like Italy, Spain and Greece.
Asia's economic growth probably troughed in the first quarter, the poll found.
Respondents refrained from slashing forecasts for the first time in a year, a positive sign although it may be too early to celebrate.
"Confidence is slowly crawling back in," said Frederic Neumann, co-head Asian economics research at HSBC.
"We have seen in China much more aggressive action has been taken to support growth, China clearly remains the regional engine, plus the financial risks we saw emanating from Europe last year have also started to dissipate."
While powerhouses China and India will not have the double-digit growth seen before the global financial crisis, both economies will rebound in 2013, supported by policy easing, robust domestic demand, reviving exports and a stabilization in the long-drawn out European debt crisis.
"The first quarter has seen the bottom in growth, things are stabilizing, and will possibly re-accelerate over the next few quarters with the region likely to hit its full stride in the second half of the year," added Neumann.
China's economy is expected to grow by 8.4 percent this year and 8.6 percent in 2013 and analysts expect growth in India to touch 7.1 percent this fiscal year, slightly lower than the 7.3 percent in the January poll.
Japan should see moderate economic growth of 2 percent this fiscal year, as rebuilding efforts on its quake-battered northeast coast and signs of recovery in overseas demand for Japanese goods contribute to a brighter outlook.
Analysts trimmed their growth expectations for Australia, New Zealand, Philippines, South Korea, Taiwan and Vietnam but the outlook for Singapore, Malaysia and Thailand had brightened, when compared to the last survey.
"The past two and a half years have taught us that Asia does not need strong growth in the G3 to grow fast itself. All Asia needs is the absence of negative growth and it will do just fine," said David Carbon at DBS in Singapore.
Central banks will continue to try and walk the tightrope between supporting growth and controlling inflation.
A swathe of better-than-expected data in the first months of the year led economists to dial down expectations for the Fed to launch a third round of quantitative easing, or QE. They put the odds of more bond purchases at 30 percent, down from the 33 percent seen in a March poll.
The Fed and the European Central Bank will hold interest rates through to the end of next year at least to support growth, as will the Bank of England - which has likely called a halt to its own asset purchase program.
In India, which was the latest central bank in Asia to ease rates, economists predict another 50 basis point cut in the repo rate to 7.5 percent by December and to 7 percent by June 2013.
While the People's Bank of China may leave lending rates untouched, it will ease liquidity and opt for selective easing targeted at smaller firms which require the most support.
"The big story for 2012 is not necessarily going to be the collapse of growth but rather how quickly inflation comes back as these economies pick up steam," said Neumann.
(Additional reporting and polling by Reuters bureau across the globe; Editing by Susan Fenton)