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SYDNEY, Dec 15 (Reuters) - Australian shares gave up early gains to hit a 2-1/2-year low led by a late sell-off in banks and resources shares after the government forecast its budget deficit would swell to A$37.4 billion ($27.1 billion) in the year to June.
The deficit for 2015/16 had been forecast at A$35.1 billion in the May budget but falling prices for key resource exports opened a gaping hole in tax revenue.
The S&P/ASX 200 index .AXJO fell for a sixth consecutive session on Tuesday, down 19 points at 4,909.60, a level last seen in June 2013. In early trades, the index rose 0.8 percent to an intra-day high of 4,969.40. It skidded 2 percent on Monday.
Earlier, minutes of the Reserve Bank of Australia's (RBA) December policy meeting reaffirmed the outlook for steady interest rates in the near term.
New Zealand's benchmark NZX 50 index .NZ50 ended up 0.09 percent, or 5.30 points, to finish the session at 6,040.55. ($1 = 1.3791 Australian dollars)