Technically, the rally stalled where it should have stalled.
The GBPUSD did the right thing. In a choppy European morning session, the price did squeeze up to the key resistance area at the 200 bar MA on the 4-hour (at 1.2393) and the key 100 day MA at 1.2405. The high reached 1.23978 between those two technical levels and sellers/profit takers came in. The pair was helped by the "people familiar" with the EU comments, but that happens. Would the GBPUSD have backed off without the comments? We don’t know, but the fact is risk could be defined and limited against those target levels. Traders sold and price came down.