The US dollar extended early Asian session's downtrend against its major rivals at the beginning of Thursday's London session.
The greenback fell to 1.6595 against the pound around 3:10 am ET, its weakest level since January 2.
The dollar slipped to 6-day lows of 0.9060 against the Swiss franc and 1.3608 against the euro around the same time.
Against the yen, the US currency hovered around the 104.20 area, the lowest level so far in the Asian session.
On the downside, the greenback may find target levels at 1.6630 against the sterling, 1.3620 against the euro, 0.9020 against the Swiss franc and 103.85 against the yen.