SPEAKER of the House of Commons John Bercow has called for progressive change after a Labour MP was forced to postpone the birth of her child to vote on the crucial Brexit bill today.

Labour MP Tulip Siddiq postponed having her caesarean section until Thursday so that she could cast her vote.

Labour colleague Harriet Harman raised the issue in an urgent question, with Bercow calling the situation "lamentable" and issuing a strong rebuke to "reactionary forces" who have delayed discussions on proxy voting.

Under proposals, MPs could have votes cast on their behalf.

Bercow said: “It really is time in pursuit of the expressed will of this House that reactionary forces are overcome and if people want to express their position let them not do it murkily behind the scenes, let them have the character to say upfront that they oppose progressive change and I hope that we can get progressive change, and what better opportunity to do so than before our historic vote.”