David Cameron gave his "full support" to the Culture Secretary Maria Miller after a Parliamentary sleaze watchdog launched an investigation into her expenses.
The probe came after The Daily Telegraph reported that the Cabinet minister claimed more than £90,000 for a second home where her parents lived.
The Minister claimed £90,718 - almost the maximum permitted - for a house where her parents had apparently been living since 1996.
Miller said two audits into her expenses had been carried out; one by former civil servant Sir Thomas Legg - who was called in to review all MPs' claims at the height of the expenses scandal - and the other by the Conservative Party.
Asked by the Evening Standard whether Sir Thomas was aware that her parents were living at her designated second home, Mrs Miller said: "I obviously spoke to the Fees Office about my claims and they were happy that everything was in order."
Miller also denied that she had used her position overseeing the post-Leveson reforms of press regulation to ward off the Telegraph.
Her special adviser, Joanna Hindley, reportedly told Telegraph reporters investigating Miller's expenses: "Maria has obviously been having quite a lot of editors' meetings around Leveson at the moment. I am just going to flag up that connection for you to think about."
This has nothing to do with the Leveson inquiry. My concern is that any investigation is done in accordance with the rules, the Editors' Code. What I did was to contact the editor of the Telegraph directly to express my concern at the way his investigation was being undertaken.
David Cameron gave his backing to the Culture Secretary, saying: "Maria Miller does an absolutely excellent job and she has my full support.
"A newspaper has asked her a number of questions and as far as I can see she has excellent answers to all those questions."
However, The Daily Telegraph has published a timeline of the sequence of events over its investigation "to set the record straight."
It has also published emails between Maria Miller and the paper's editor Tony Gallagher.