​May told a meeting of Conservative lawmakers she would stand down if her divorce plan finally got through a bitterly-divided parliament, to ensure a smooth path for a new leader to begin the next step of negotiating the future relationship with the European Union.

from Times of India https://timesofindia.indiatimes.com/world/uk/theresa-may-says-shes-ready-to-quit-if-her-brexit-deal-is-passed/articleshow/68605639.cms