What will be the effect of a no-deal Brexit if Britian is unable to agree an extension to the withdrawal process with the European Union?
May has promised to report back to parliament on her negotiations with the EU, when lawmakers are expected to hold a second vote on the Brexit deal.
Queen Elizabeth II has emphasised the need for Britons to come together to "seek out the common ground", in what is being viewed as an appeal to overcome bitter divisions over Brexit.
The British prime minister is expecting the European Union to give further clarification on the backstop arrangement to maintain an open Irish border after Brexit.
British Prime Minister Theresa May has defended her anguished draft divorce deal with the European Union before rowdy lawmakers and a splintered cabinet that threatens to fall apart.