MARIA Miller has said she takes full responsibility for her decision to stand down as Culture Secretary, saying that she did not want to become a distraction from the achievements of the Government.

She said she had hoped to carry on in office after she was cleared of the central expenses allegation against her by the Commons Standards Committee but it had become clear it was impossible to do so.

"This has been a really difficult 16 months. Because I was cleared of the central allegation made about me by a Labour Member of Parliament, I hoped that I could stay. But it has become clear to me that it has become an enormous distraction," she said.

"It is not right that I am distracting from the incredible achievements of this Government. 

Asked if she had been pressurised into quitting, a clearly emotional Mrs Miller said: "I take full responsibility for my decision to resign. I think it is the right thing to do to remove what has become really an unhelpful and very difficult distraction for colleagues."

Asked also whether she believed she had been the victim of a media witch hunt because of her role in implementing the recommendations of the Leveson Inquiry on press standards, she said: "I take full responsibility for the situation. I fully accept the findings of the parliamentary standards report. This is about that."

David Cameron reluctantly accepted her resignation after almost a week of backing Ms Miller over an expenses row.

The Prime Minister has replaced her with Sajid Javid, who has been promoted from his ministerial role at the Treasury.

The Bromsgrove MP, a former managing director at Deutsche Bank, has long been tipped as a rising star in the Conservative Party and has served as Financial Secretary to the Treasury since last October.

Nicky Morgan is stepping up from her role as Economic Secretary to the Treasury to replace Mr Javid, the Prime Minister said.

Amid signs that support from her colleagues was ebbing away, Mrs Miller issued another apology last night, admitting she had "let people down" in the way she aproached parliamentary standards commissioner Kathryn Hudson's probe into her accommodation expenses.

But she insisted the standards committee had dismissed the allegations against her - even though it ordered her to repay £5,800 in overclaimed mortgage interest and say sorry on the floor of the House.

The minister also avoided referring to Ms Hudson's recommendation that she should hand back £45,000, a conclusion that was overruled by the cross-party MPs.

Former Commons speaker Baroness Boothroyd became the latest senior figure to demand Mrs Miller's departure, saying it should be a "matter of honour".

"She is bringing Parliament into disrepute," Lady Boothroyd said. "I think the vast majority of people in this country, if they were asked, would have the same feelings that I have."

Anger on the Conservative benches has focused on Mrs Miller's "perfunctory" 32-second apology in the Commons last Wednesday and her obstructive approach to the commissioner's inquiry. There are fears the row could reignite public anger over expenses and undermine the party's prospects in forthcoming local and European elections.

Mrs Miller's article in the Gazette was 178 words long, compared to the 79 words in her apology to the Commons.

Tory MP Mark Field was among those openly voicing concerns yesterday, saying: "There is this whole public perception here that, rightly or wrongly, the Standards Committee as it is currently constituted is somehow open to being nobbled by senior government members.

"In many ways it is that public perception that is so damaging here. It led to what many people regard to be an unacceptably perfunctory apology from Maria Miller."

Another Conservative, Zac Goldsmith, said: "It would be the Prime Minister's decision who he surrounds himself with. I am surprised that Maria Miller hasn't stepped down."

Backbencher Philip Davies said the continuing row over Mrs Miller was"extremely damaging" for the Conservative Party and needed to be resolved as soon as possible.

"Whether she resigns is a matter for her but obviously the whole thing is extremely damaging for the Conservative Party, it's damaging for Parliament as a whole and politicians - we all get tarnished by the same brush," he said.

Earlier this week work and pensions minister Esther McVey distanced herself from Mrs Miller, saying "it wouldn't be how I would have made an apology". Thurrock MP Jackie Doyle-Price, whose seat is one of the most marginal in the country, said Mrs Miller should not expect colleagues to speak out in her favour.

Labour leader Ed Miliband has sought to capitalise on the situation, warning that Mr Cameron has "serious questions to answer".

Pressure for fundamental reform at Westminster was strengthened after the three outside members of the Standards Committee - brought in to improve the way MPs are held to account - called for a rewrite of the existing code of conduct. The three lay members complained that the issue was not taken seriously enough - with some committee meetings having to be abandoned because no MPs turned up - while the system allowed politicians to "ignore the spirit of the law".

But despite the PM's declaration that he was open to further reform, Mr Lansley warned MPs that making the standards watchdog fully independent would compromise parliamentary privilege and make the job harder to do.