Politicians now see TV and radio interviews as “all risk” and almost “no opportunity”, veteran BBC journalist Nick Robinson has said after Liz Truss cancelled an interview with him at the last minute.

The frontrunner to become the next prime minister was due to be quizzed by Robinson in a face-to-face interview due to be broadcast at 7pm this evening on BBC One.

However, she pulled out because she could “no longer spare the time”.

Asked what events she was taking part in on Tuesday, her campaign said there was “nothing to flag today”.

A source from Ms Truss’s campaign said she is not taking part in the interview, which she had agreed to, as she is focusing on winning as many votes as possible and preparing for government.

Writing for the BBC, Robinson noted politicians and advisers increasingly see TV and radio interviews as “all risk and almost no opportunity”.

He said he suspects that Ms Truss has “yet to finalise her plans” on the cost-of-living crisis and is “reluctant to have that demonstrated on TV in front of an audience of millions”.

Robinson added: “The BBC doesn’t believe it is entitled to interview those who govern or want to govern us.

“I’m all too aware of the huge pressure politicians, and their often very small teams, face.

“However, I do want to say why broadcast interviews matter for the health of our democracy.

“That may sound impossibly grand, so let me explain.

“In this contest, tens of millions of people have had no say in the choice of their own leader.

“They want to see and hear their leaders questioned, challenged and tested.

“That’s all very well, politicians and their advisers shout as they read that last sentence.

“But they increasingly see TV and radio interviews as all risk and almost no opportunity.”

Robinson said politicians and advisers claim interviews are no longer about “engaging in a grown-up conversation” and that, instead of watching the interviews live, many “view short excerpts on social media which are usually gaffes or grandstanding questions by preening interviewers”.

The veteran BBC journalist insisted this is “up to a point”, as “about two million people watched my BBC One interview with Rishi Sunak” and “some seven million listen to the big interviews on the Today programme”.

He added: “What they want to hear is an argument being made about what a leader can do to address the issues that shape their lives.”

Robinson concluded: “Democracy requires the consent of the people, even those who didn’t vote for you or disagree with your policies.

“Good government requires accountability.

“Restoring trust in politics requires openness about how and why decisions have been reached.

“That is, in large part, the job of Parliament, not TV and radio interviewers like me.

“However, what we do has a role to play too.

“In recent years, it’s become fashionable to say that that sort of political dialogue is no longer possible.

“The in-depth political interview is dead, say some.

“Boris Johnson hated them.

“Theresa May and Jeremy Corbyn weren’t much keener.

“I hope and believe they are wrong.

“That’s why I look forward to an in-depth interview with our next prime minister, whether it’s Liz Truss or Rishi Sunak.”

Speaking later on the BBC’s The One Show, Mr Robinson said he had hoped to ask Ms Truss the questions that viewers want to know.

“What I want to do with an interview is, I think, ask the questions that your viewers want to know,” he said.

“Am I going to get help? Am I going to get help however well off I am?

“Will I get help if I’m a pensioner? Will I get help if I’m on benefits?

“Will I get help if I’m not old and I’m not that poor? But even though I might be earning money, like a teacher, I’m on 30, 40, 50,000, I’m not poor, but I might be thinking good God, the doubling up of my energy bill – I just can’t afford it.”

He added that he wanted to ask Ms Truss how she intends to help people.

“Is it money directly in the way that Rishi Sunak, the other candidate, says?” he said.

“I got the chance to put those questions to him when he came on BBC One and I haven’t got a chance to put those to her.”