Analysis by David Cornock, BBC political correspondent
Both Rishi Sunak and Liz Truss believe they are on the right side of the moral argument over the cost of living crisis that is dominating this leadership election.
Liz Truss argues that putting up taxes is immoral - but Rishi Sunak told Nick Robinson the government had a "moral responsibility" to go further to help those who cannot afford to heat their homes.
He suggested bills could be £400 higher than anticipated when he was chancellor. How much further would he go? Anyone hoping for specific figures will have to wait but there were strong hints of targeted help for pensioners and those on the lowest incomes.
This interview may be seen and heard by millions but both candidates have tried, to varying degrees, to target their message at the 160,000 or so Conservative Party members who will choose our next prime minister.
Mr Sunak, the self-styled underdog in this contest, appeared to acknowledge that those members may prefer to hear Liz Truss's message on tax cuts.
He said he went into the contest prepared to tell people to tell people "what they needed to hear rather than what they needed to hear, not necessarily what they wanted to hear".
That doesn't mean he hasn't refined his own message during the campaign - he's promising to cut VAT on energy bills, a position he rejected in government - but he made clear he would rather lose (or win) on his own terms.