Prime Minister Theresa May is aiming to break the parliamentary deadlock over Brexit by proposing to seek further concessions from the European Union on a plan to prevent customs checks on the Irish border.
On Tuesday, Parliament will debate May's proposed next steps as well as alternative plans put forward by lawmakers, including some that seek to delay Britain's March 29 exit by requesting an extension to the two-year Article 50 negotiation period.
Others seek to shift control of the process away from government and give Parliament itself the chance to define Brexit. If successful, this could have a profound effect, giving lawmakers who want to block, delay or renegotiate Brexit a possible legal route to do so.