LONDON (AP) — Two prominent Brexit backers are warning Prime Minister Theresa May not to seek a delay to Britain's scheduled March 29 departure from the European Union if her withdrawal deal is rejected Tuesday.

Conservative Party lawmaker Steve Baker and Democratic Unionist deputy leader Nigel Dodds wrote in the Sunday Telegraph that prolonging the Brexit process rather than making a clean break would lead to "political calamity."

The two said slowing Britain's departure would mean a "costly delay" for British businesses and irreparable damage to public trust in politics.

Brexiteers who are ready to embrace a "no deal" Brexit if no agreement is approved by Britain's Parliament worry that a possible vote this week to seek an extension of the talks will eventually lead to a softening or cancellation of Brexit plans.