Tory leadership rivals have clashed in a live BBC TV debate on whether the UK can leave the EU, no matter what, by the October 31, deadline.
Asked for a guarantee he would do this, Boris Johnson described the deadline as “eminently feasible”.
Sajid Javid said it “focused minds”, but Michael Gove and Jeremy Hunt said extra time might be needed.
Rory Stewart accused his colleagues of lacking realism – of “staring at the wall and saying ‘believe in Britain'”.
The five men vying to be Conservative Party leader – and the UK’s next prime minister – were taking part in a live BBC televised debate on Tuesday night.
Former Brexit Secretary Dominic Raab was earlier eliminated in the second round of voting, when Conservative MPs held a secret ballot.
The third round of voting will take place later, between 15:00 and 17:00 BST.
The result is expected at 18:00 BST and the MP with the lowest number of votes will be out of the race.
During Tuesday’s hour-long debate, all five men ruled out calling a general election until Brexit was resolved.
But the encounter exposed divisions in their approaches to Brexit and whether they could accept the UK leaving the EU without an agreement.
The candidates, who faced questions from members of the public on issues ranging from climate change to Islamophobia, also disagreed over whether to prioritise tax cuts or increased spending on public services after the UK leaves the EU.
Mr. Johnson, the frontrunner in the contest, was taking part in his first debate of the campaign after he skipped Sunday’s Channel 4 encounter.
