Sterling on Friday was headed for its worst weekly decline since October with a stalemate over Brexit weighing on the currency and leading the Bank of England to cut its growth forecast.
The pound was volatile on Thursday. It fell after the BoE kept interest rates on hold and then strengthened when the central bank said rates will rise if an EU divorce deal is done.
That was seen as somewhat hawkish a time when other major central banks have said they will hold off from raising borrowing costs.
The pound fell 0.2 percent to $1.2935, after dropping as low on Thursday as $1.2854, a two-week low. It has lost over 1 percent of its value this week.
Against the euro, it traded flat at 87.56 pence.
May will return to parliament on Feb. 14 for a debate on the Brexit negotiations, when lawmakers could again try to wrest control of the process from her, but a vote on approving the Brexit deal is likely to come later in the month.