The Queen is to face a public inquiry into her expenses by parliament's most powerful watchdog, it has emerged.
The Public Accounts Committee is to be handed powers to scrutinise the finances of the Royal Family after an overhaul in laws governing royal expenses.
The move is likely to cause consternation at Buckingham Palace, with aides to the Queen facing a public grilling by MPs over whether the Royal Family provides value for money to taxpayers
The committee has gained a reputation for its damning criticisms of civil servants deemed to have misused public funds.
The cost of supporting the Royal Family rose by 16 percent last year, despite deep cuts elsewhere across the budget.
The committee, chaired by former Labour minister Margaret Hodge, will decide on the scope of the inquiry after the National Audit Office gains access to the Queen's finances next month.
Committee sources indicated they are likely to call palace officials to give evidence, based on auditors' findings.
Austin Mitchell, a Labour MP who sits on the committee, told the Independent. "I'm all in favour of it. It's not intrusive. It is about ensuring that the public are getting good value for money.
"At the moment there is no accountability for spending what is a considerable fortune."
Another source said: "Margaret wants to do it, but obviously it's got to be a decision of the whole committee."
Funds earmarked for junior royals are likely to be among the first cuts to be recommended.
Other costs associated with the Royal Train and the Royal Flight, as well as funds spent on official functions and palace upkeep, will fall under close scrutiny.
Questions may also be raised over whether the Queen is doing enough capitalise on the royal brand, with some arguing that Buckingham Palace should be open to paying visitors all year round, rather than only in summer.
Other royal castles at Sandringham and Balmoral remain closed to the public all year round, despite the millions of pounds spent on their maintenance.
The inquiry follows George Osborne's decision to scrap the Civil List, the annual handout to the Royal Family that has been approved by Parliament since 1760. Instead, the Queen will be paid 15 per cent of the income from the Crown Estates as a "Sovereign Grant".
Crown Estate assets include Regent Street in London, Ascot racecourse and Windsor Great Park, 265,000 acres of farmland, as well as ownership of the national seabed stretching 12 nautical miles around Britain.
In April 2013, Buckingham Palace will receive £36.1m to fund the Queen's official duties, representing a 16 per cent increase on the £31m paid by taxpayers in 2012.
The inquiry is likely to call Sir Alan Reid, the Keeper of the Privy Purse - the Queen's treasurer - to be questioned by MPs on live television. Sir Christopher Geidt, the Queen's private secretary, will also be summoned to give evidence.
The committee has gained a fearsome reputation after roundly condemning executives of Amazon, Starbucks and Goldman Sachs over their tax affairs.
It has also grilled Whitehall mandarins over their tax affairs, and departmental spending waste.
This week, MPs on the committee accused the Department of Work and Pensions of causing "misery and hardship", the Department of Health of "abject failure" and the Department of Energy of "failing to get to grip" on Britain's nuclear waste.
A committee source said: "We will be looking into the royals later this year. We need to be sure when other public services are being cut that there is value for money. We would certainly want to speak to the most senior people who control the purse strings."
Buckingham Palace declined to comment.