The candidates for the Conservative leadership have not acknowledged “how bad things are in the country” and the Tory party, according to former prime minister Liz Truss.

Ms Truss said that the four MPs vying to be Rishi Sunak’s successor have to “explain what went wrong”.

Kemi Badenoch, Robert Jenrick, Tom Tugendhat and James Cleverly are trying to drum up support from their colleagues and party members at the Conservative Party conference in Birmingham.

Speaking at an event at the conference on Monday, Ms Truss also said she thought the party would have fared better in July’s general election if she had still been leader rather than Mr Sunak.

She told the in-conversation event: “So far, I haven’t seen any of the candidates really acknowledge how bad things are in the country as a whole, and frankly, for the Conservative Party.”

“They think ‘all we need to do is show competence and we will be ushered back into office’,” Ms Truss said, adding: “They have to explain what went wrong, why things are so bad for the Conservatives and what they’re actually going to do.”

Migration, the NHS and the future of the Conservative Party are among the topics the leadership candidates are discussing with members at the Birmingham gathering.

Mr Jenrick has said he wants to “get migration done”, echoing former leader Boris Johnson’s language on Brexit.

Former immigration minister Mr Jenrick – who quit Mr Sunak’s government after pushing for tougher measures over the Rwanda asylum scheme – is advocating for a cap on legal migration in the tens of thousands or fewer and for a stronger version of the Rwanda policy.

He told a breakfast rally on Monday morning: “If we have that cap, then we can stop talking about migration.

“I want to get migration done.

“This is a running sore in British politics.

“It’s important that we settle this by having serious answers to these challenges.

“Then we can talk about all the other issues that the public wants us to be discussing, like the economy and the NHS.”

However, Mr Cleverly said that those offering a simple solution to tackling migration “don’t know what they are talking about”.

Reflecting on his time as home secretary, he said that “under my watch” the “asylum rejection rate went up, our deportation rate went up, our net migration came down”.

Mr Cleverly added: “I gobbed off less and delivered a bucketload more.

“That is what gets us back into office, and anyone who sits here in front of you or on a stage wherever and says the simple solution is to do this one thing, they either don’t know what they are talking about or they hope you don’t know what you are talking about.”