Boris Johnson and Jeremy Hunt are preparing for the second and final head-to-head debate of the Conservative leadership campaign.
They will face 90 minutes of questions from Sun newspaper readers.
The event, starting at 19.00 BST, will be streamed live on the newspaper’s website and broadcast on Talk Radio.
The result of the contest to succeed Theresa May as prime minister will be announced on 23 July, with the winner taking office a day later.
Voting in the postal ballot to choose the next Tory leader began about 10 days ago.
It is estimated that well over half of the 160,000 or so Conservative Party members eligible to take part have already returned their ballot papers.
In Monday’s debate, billed by the newspaper as The Final Showdown, the two