Senior minister David Lidington said May had clinched changes to her Brexit agreement in a bid to win last minute support before it goes to a vote on Tuesday.

May has secured "legally binding changes that strengthen and improve the Withdrawal Agreement and Political Declaration," Cabinet Office Minister Lidington, who is May's de facto deputy, told parliament.

The pound jumped as high as $1.3290 in Asia, having been as low as $1.2945 at one stage on Monday. It was last trading at $1.3237.

The euro slid to its lowest on the pound since mid-2017 around 84.71 pence, and was last quoted at 85.14 pence.