The Australian sharemarket suffered its biggest fall of the year, led down by the big banks amid growing doubts the Reserve Bank of Australia will cut interest rates next week, as a surge in the Australian dollar worried investors. The S&P/ASX 200 closed down 109.94 points, or 1.85 per cent, to 5838.6, while the broader All Ordinaries fell 103.25 points to 5818.2. The Australian dollar hit a three-month high of US80.25 overnight, as the greenback weakened and investors speculated the recent run of stronger-than-expected local economic data and the iron ore price rally could stay the RBA board's hand next Tuesday.