Explaining why he could not back frontrunner Boris Johnson, the ex-PM said he could never vote for someone who “misled the country” in the EU referendum campaign.
Sir John, who served as PM from 1990-97, was a prominent voice for Remain in the 2016 referendum and has given his support to calls for a second public vote on EU membership.
He told the BBC’s HardTalk: “A ballot is private, but I think it is fairly evident from my views that I cannot vote for someone who was part of the Brexit campaign that misled the country.
“So I shall offer my vote to Jeremy Hunt. I don’t think anyone would be in any doubt about that.”
Sir John said he had not yet received his ballot paper. The first voting slips started arriving on doorsteps of Conservative party members on Thursday, and the bulk of the 160,000 activists eligible to vote are expected to return them over the coming days.
But the former PM urged them to hold back on casting their vote until they have seen the two candidates go head-to-head in a televised debate.
The only two debates which both have so far signed up to are being hosted by ITV on 9 July and The Sun on 15 July, longer after many members will have voted.
Sir John said: "I hope everybody, before casting their vote, will wait a little while.
"We need to see the two candidates properly examined by the mieda. We need to see both candidates appearing before the meida, answering the difficult questions, explaining what they will do, explaining how they will do it."
Outgoing PM Theresa May has declined to reveal who she will back in the race to find her successor, or who she voted for in the series of MPs’ ballots at Westminster.
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