British Prime Minister Theresa May has warned Tory rebels seeking to wreck her blueprint to leave the EU that they could be left with "no Brexit at all" unless they fall into line.
She said a threatened Commons revolts by pro- and anti-EU MPs risked undermining any chances of a deal with Brussels.
In an article for The Mail on Sunday, she called for MPs to take a "practical and pragmatic" approach rather than face a "damaging and disorderly" Brexit.
May acknowledged some MPs had concerns about her plan for a "common rule book" with the EU for goods and customs traded within what she called a new "UK-EU free trade area".
However, she insisted that she had yet to see a "workable alternative" to the proposals - agreed by the Cabinet at Chequers - that would ensure trade remained as "frictionless" as possible while avoiding the return of a hard border between Northern Ireland and the Republic.
"We need to keep our eyes on the prize. If we don't, we risk ending up with no Brexit at all," she said.
"I know there are some who have concerns about the 'common rule book' for goods and the customs arrangements which we have proposed will underpin the new UK-EU free trade area. I understand those concerns.
"But the legacy of Brexit cannot be a hard border between Northern Ireland and Ireland that unpicks the historic Belfast Agreement.
"It cannot be the breaking up of our precious United Kingdom with a border down the Irish Sea. And it cannot be the destruction of integrated supply chains and just-in-time processes on which jobs and livelihoods depend."
