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SYDNEY, March 21 (Reuters) - Australian shares reversed early gains to finish down 0.2 percent on Thursday, as upbeat Chinese manufacturing data for March was offset by political uncertainty as Prime Minister Julia Gillard faced a leadership challenge.
Rivals called on Gillard for a ballot to resolve months of slipping polls and internal tensions that put her minority Labor government on course to be swept away at September elections.
"This move has, and will continue to increase the political risk in Australia," said Chris Weston, chief market strategist at IG Markets.
"This will cause jitters in the local market which can be seen by an initial fall in the ASX200."
The S&P/ASX 200 index 8 points lower at 4,959.4, a fourth consecutive session of losses. The dip reversed intraday gains that saw the index reach 4,998.9 points. The benchmark fell 0.4 percent on Wednesday.
"The untenable position the government currently holds can only serve to remind overseas investors of the political uncertainty and risk inherit in our market," said Ben Taylor, sales trader at CMC Markets.
The Australian market has risen around 7 percent this year, buoyed by a relatively strong earnings season, upbeat domestic data and signs of improvement in the global economy.
Billabong tumbled 14.2 percent to an all-time low of A$0.70 on Thursday amid concerns about the status of two rival $544 million bids for the company.
Gold miners weighed on the market after the bullion slipped on Wednesday in response to the U.S. Federal Reserve's pledge to maintain its accommodative policy stance to support the economy. Newcrest Mining and Resolute Mining Ltd lost 2.4 percent and 2.2 percent respectively.
Data earlier in the day that showed a pick up in manufacturing activity in China, Australia's biggest export market, helped contain broad market losses.
The data drove up some of the big mining and steel stocks. Rio Tinto Ltd advanced 1.4 percent, while Fortescue Metals Group soared 2.9 percent. Bluescope Steel jumped 4.3 percent.
BHP Billiton Ltd bucked the trend, losing 0.4 percent.
Elsewhere, food retailer Woolworths Ltd lost 0.7 percent, rival Wesfarmers declined 2 percent and top telecommunications provider Telstra traded flat.
Financials were mixed, with Australia New Zealand Banking Group and Westpac Banking Corp up 1.1 percent and 0.5 percent, respectively, while top lender Commonwealth Bank of Australia fell 0.7 percent.
New Zealand's benchmark NZX 50 index slipped 0.2 percent or 6.9 points to 4,342.5.
(Reporting by Thuy Ong; Editing by Shri Navaratnam)