A Tory MP has described David Cameron and George Osborne as "two arrogant posh boys" with "no passion to want to understand the lives of others".
Nadine Dorries told the BBC's Daily Politics their "real crime" was to show "no remorse" about their lack of insight beyond Westminster.
Last year, Mr Cameron apologised to Ms Dorries for the way he responded to her at PM's questions.
But he said he did not "accept" her latest criticism.
Earlier this year, Mid-Bedfordshire MP Ms Dorries told the Financial Times that government policy was "being run by two public school boys who don't know what it's like to go to the supermarket and have to put things back on the shelves because they can't afford it for their children's lunch boxes"
"What's worse, they don't care either," she added.
Mr Cameron later described her comments as "nonsense".
Cost of a pint
Speaking to BBC2's Daily Politics on Monday, Ms Dorries was asked whether she still believed the prime minister and chancellor were "two posh boys who don't know the price of milk".
She replied: "There is a very tight, narrow clique of a certain group of people and what they do is they act as a barrier and prevent Cameron and Osborne and others from really understanding and knowing what is happening in the rest of the country.
"Unfortunately, I think that not only are Cameron and Osborne two posh boys who don't know the price of milk, but they are two arrogant posh boys who show no remorse, no contrition, and no passion to want to understand the lives of others - and that is their real crime."
In an interview with the BBC's political editor Nick Robinson, Mr Cameron said: "I don't agree with Nadine. She's got a very strong view about a number of things...
"You're always going to have MPs who don't agree with you. and you can either spend your entire time trying to appease them in some way, or you can actually say, look, you may not agree with everything I'm doing, but I'm doing the right job on behalf of the people of this country."
The prime minister said he did "a lot of the family shopping" and often went to Sainsbury's in his Chipping Norton constituency "on a Friday or a Saturday".
Asked if he knew the price of a pint of milk, he replied: "Just under 50p."
Speaking later to BBC Look East, Ms Dorries said her words were "a shot across the bow" to the Tory top brass.
"What I said was speak directly into the heart of Number 10, and to the leadership who have become slightly disconnected from the rest of the people who are working very hard for true Conservative values and causes."
She said the main problem was that Mr Cameron saw himself as "a social liberal" and "I don't think there's a Conservative councillor in the land who describes themselves as a social liberal."
However, Ms Dorries denied any suggestion she was considering a defection to the UK Independence Party.
Following her comments, the MP's local Conservative Association chairman Paul Duckett said in a statement: "Nadine Dorries MP has expressed her personal opinions and it would have been courteous of her to advise the association prior to expounding them."
Last September, Ms Dorries campaigned for an amendment to the Health and Social Care Bill, which would have stopped abortion providers giving NHS-funded counselling to women.
She claimed Mr Cameron dropped his support for it after pressure from Nick Clegg, and during PMQs, urged the PM to show his deputy "who's the boss".
The prime minister, struggling to get his reply out amid laughter from Labour MPs, replied: "I know that the honourable Lady is extremely frustrated about the... perhaps I should start all over again... I am going to give up on this one."
Downing Street insisted the prime minister had not intended any innuendo in his reply to Ms Dorries, and she later told the BBC's Newsnight he had contacted her personally to apologise.