Royal Bank of Scotland - "GBP was hit close to the end of last week with a Moodys downgrade from Aaa to Aa1. Even though hardly a surprise, the GBP remains weaker in early Asia trading. The key to sentiment this week will be how it trades through the open in European hours.
GBP/USD is trading below a region of previous support around 1.5230/1.5350 made over 2010/12. It closed below this region last week, dropping sharply on the Moodys announcement right near the end of the week's trading. If it remains below this region through the Monday trading session it should encourage thoughts of a much deeper fall, with little support until 1.4780."