GBP/USD is under fresh pressure as May meets with European leaders in Brussels. They're delivering a message that she needs to get a vote before parliament on a deal before they will grant an extension.
There is increasing talk that May won't be able to get the ERG and DUP on board and is looking to Labour. If she can't win in the next vote (if Berkow even lets her have it), then it's going to create massive uncertainty.