1053 GMT - The Japanese yen could weaken if the Bank of Japan fails to signal interest rates will rise as much as markets expect in a decision Friday, MUFG Bank's Derek Halpenny says in a note. The BOJ is widely expected to deliver a 25 basis-point rate rise and could indicate plans to raise rates further, he says. "That said, there is a notable risk that BOJ Governor Kazuo Ueda's comments could fall short of what markets are expecting given 90 basis points of hikes are priced over the next 12 months." Ueda has history of being cautious when global uncertainties rise, he says. The dollar falls 0.4% to 155.61 yen.