The local share market has suffered its worst loss in more than a month on fears the Middle East conflict could delay US interest rate cuts, even after President Donald Trump extended a ceasefire with Iran at the request of Pakistani mediators.

The benchmark S&P/ASX200 index on Wednesday fell 105.8 points, or 1.2 per cent, to 8,843.6, its worst single-day loss since a 142-point fall on March 19.

The broader All Ordinaries dropped 102.8 points, or 1.12 per cent, to 9,074.3.

The Australian dollar was trading for 71.69 US cents, from 71.63 US cents at 5pm on Tuesday.