Theresa May is to meet the chairman of an influential committee of backbench Tory MPs, Sir Graham Brady, amid calls for her to set a firm resignation date, ONA reports citing BBC.
It follows a request from the 1922 Committee for "clarity" on the issue.
No 10 insists the meeting is routine, but pressure is mounting on the PM, with local Tory associations confirming they will hold a vote of confidence in her leadership on 15 June.
Meanwhile, cross-party talks to break the Brexit deadlock are due to resume.
In March, Mrs May pledged to stand down if and when Parliament ratified her Brexit withdrawal agreement with the EU - but she has not made it clear how long she intends to stay if no deal is reached.
The UK had been due to leave the EU on 29 March, but the deadline was pushed back to 31 October after Parliament was unable to agree a way forward.