On a 4-hour chart the GBP/USD formed the combination of candlesticks Bearish Engulfing that indicates the downside movement.
This combination of candlesticks emerged after the currency pair could not break out the resistance level near 1.6085-1.6096. This means that the bulls did not manage to solidify here, and further the bears started to increase their influence.
The breakout of 1.5841 will confirm this viewpoint. In this case the decline with the target to 1.5651 is expectable.
However, it should be mentioned that if the resistance level of 1.6096 is broken out then short positions should be closed, as it will lead to the increase to 1.6175.