The Australian bourse finished flat on Tuesday, with gains in financials opposed by falls in the big miners.

Mining stocks fell a little after key independent MPs Tony Windsor and Rob Oakeshott handed the Labor Party the numbers to govern Australia for the next three years.

The benchmark S&P/ASX200 index closed down 2.3 points or 0.1 per cent at 4573.2. The broader All Ordinaries index slumped 2.7 points, or 0.1 per cent, to 4613.

Among the sectors, materials shed 0.3 per cent, while financials added 0.3 per cent. Energy shares improved moderately, gaining 0.1 per cent.

The local market dipped minutes after two key independent MPs said they would back the Labor Party. But shortly afterwards the All Ordinaries and S&P/ASX200 pared back some of these losses.

The bourse was initially unhappy with the independents' decision but then supported the move, according to Austock Securities senior client adviser Michael Heffernan.

Mr Heffernan said, ''I think what the market is happy about is that there is going to be a lot more discussion in this parliament about various issues than there was in the past."

The major miners dipped slightly, as expected, given Labor's proposed mineral resource rent tax (MRRT).

BHP Billiton shed 11 cents at $38.44 and Rio Tinto gave off 65 cents at $74.35. Fortescue slid down 0.2 per cent to $4.93.

The big four banks, meanwhile, all posted gains, with Westpac the best performer after looking up 25 cents or 1.1 per cent to $23.03.