AUSTRALIAN bond futures prices are slightly lower ahead of a key speech by US Federal Reserve chairman Ben Bernanke. Westpac interest rate strategist Tim Jung said it had been a relatively quiet trading session as the market focused on the pricing of new Australian government bonds. The Australian Office of Financial Management on Wednesday priced its new 21 April 2025 Treasury Bond at a yield to maturity of 3.47 per cent. "That has been dominating the market's attention today," Mr Jung said. He said Dr Bernanke's speech would be the key focus for markets overnight, with some expecting the Fed chairman to signal the central bank would start to wind back its stimulus program. Mr Jung said Dr Bernanke was likely to disappoint those expectations and traders were likely to take a cautious approach in the lead up to the speech. "We expect the market to be pretty contained heading into that," he said. At 1630 AEST on Wednesday, the June 10-year bond futures contract was trading at 96.730 (implying a yield of 3.270 per cent), down from 96.745 (3.255 per cent) on Tuesday.