Sterling has fallen to a three-year low against the euro after Theresa May outlined the timetable for starting Brexit negotiations.
It also hit its lowest level against the dollar since the beginning of July.
On Sunday, the prime minister said she would trigger Article 50, the clause needed to start the process, by the end of March 2017. That means the UK is likely to leave the EU by mid-2019. In early morning trade, the pound fell by about 1% against the euro to €1.1433 before recovering slightly.
It was also down 1% against the dollar at $1.2854 at one point, its lowest since 6 July, when it hit $1.2797.