Jeremy Hunt has said he would back a no-deal Brexit with a “heavy heart” but would, unlike Tory rival Boris Johnson, not commit to a deadline for leaving.
He told the BBC leaving the EU was a “democratic promise” that must be kept, whatever the economic repercussions.
But he said the quickest way to leave was via a new deal and guaranteeing a specific exit date was a “fake debate”.
The leadership candidates have also defended their plans to spend billions on education, defence and transport.
Mr Johnson, who is the frontrunner in the race to be the new Conservative leader, and the UK’s next prime minister, told Sky News he would be prepared to borrow more to spend on vital national infrastructure.
He told the Sophy Ridge programme there was about £25bn “available” immediately from the Treasury which he would use on public services rather than reducing the deficit.
Mr Hunt told the BBC’s Andrew Marr Show he would use the “war chest” built up by Chancellor Philip Hammond, arising from the improved state of the public finances.
But he conceded some of his spending priorities would “have to wait” if the UK left without a deal – as the money would be needed to support businesses affected.