There is a resistance area around 1.6600 that has been tested recently and it appears as though the pair may be moving down to test the lower diagonal trend line support level.
The GBP/USD is going to experience an important trading day today as there are 4 major news announcements coming out that will impact this pair. The Dollar has had great pressure against it over the last few days and this be a short pullback but the news events of the day will give direction to this pair. There could be a great deal of volatility today with this many news announcements, so keep that in mind when making trading decisions for today.
The next resistance level after the 1.6600 area is 1.7051 on the daily chart so if the 1.6600 level gets passed that will be the next target. If the lower diagonal If the lower diagonal trendline gets passed to the downside the next support target is 1.6113
The daily chart there is an ascending triangle forming so when the pair is ready to break out of that triangle that could indicate a major price move ahead.