Cable initially rallied when PM May announced she would step down as Conservative Party leader on June 7, but the celebration was brief as the market saw the event as the beginning of a new period of Brexit uncertainty that will cast a pall over the UK economy and the pound.
The pair rose to 1.2719 and has since fallen back near its pre-announcement levels in the mid 1.26's.
GBP bulls need a rise above the falling 10-DMA at 1.2763 to remove the existing bearish tone, with a move above the 200-DMA at 1.2956 giving GBP/USD bulls momentum.
Today's development leaves an assortment of Brexit options on the table once the new PM takes over nL5N2302BY, including second referendum, general elections and no-deal exit.
If worries over a no-deal Brexit and new general election pick up, GBP/USD finds light support at Thursday's low of 1.2605 and the lower 30-week Bolli at 1.2553.
More firm support is at 1.2409, the Jan. 3 and 2019 low.
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