At the highest levels of US trading. The earlier spike higher came on a reported 500m euro order from a US custodial shop. All the talk is about flows in EUR/GBP, with specs targeting stops above 0.8400/06.
The trade here is to go with the flow. If 0.8400 breaks, there are pips to be made on the upside. If it holds, pile into shorts.
It should be a good battle.