Prime Minister Theresa May is making a last-ditch attempt to persuade MPs to back her Brexit deal as Tuesday's key Commons vote looms closer, BBC reports.
She will use a speech on Monday to warn that Parliament is more likely to block Brexit than let the UK leave without a deal.
Mrs May will add that trust in politics will suffer "catastrophic harm" if the referendum result is not implemented.
Labour has vowed to table a vote of no confidence if Mrs May loses.
Its leader Jeremy Corbyn said Labour would vote against the deal and would start moves to trigger a general election if it is voted down.
He told the BBC's Andrew Marr show: "We will table a motion of no confidence in the government at a time of our choosing, but it's going to be soon, don't worry about it."