Tony Blair is facing calls for an inquiry into allegations he got special treatment from Britain's top taxman and senior staff when setting up a secret trust to run his multi-million business empire.

Former Home Secretary David Davis called for the probe after the man who set up the former Prime Minster's business affairs claimed head of HMRC Dave Hartnett was approached for advice.

Two of Blair's advisers claimed they had access to senior HMRC staff when setting up his trust before he left office, and were able to ask how they would be treated for tax purposes.

Trust me: Former prime minister Tony Blair says he paid full UK tax - and 'did not set up this structure for reasons of tax advantage'

The advice came from senior advisers that normal taxpayers 'wouldn't get anywhere near', according to a leading tax QC, and helped him avoid tax on his multi-million pound business empire.

Mr Davis said he would write to the Commons public accounts committee calling for ‘an inquiry into special treatment of high-profile individuals by HMRC,' he told The Times.

He added: ‘These arrangements appear to have been put in place without any proper scrutiny, and are not available to ordinary taxpayers’.

Blair's empire - which includes £32million in property - is managed through more than a dozen trusts and companies, which his advisers claim is done for privacy purposes.

Talking to undercover reporters from The Times, the adviser boasted that the trust was so shrouded in secrecy that the Guardian newspaper had 'crawled all over it for ten year' and still not cracked it.

He described Mr Hartnett, famous for offering 'sweetheart' tax deals to companies including Starbucks and Vodafone, as 'quite approachable'.

THE 'PUBLIC SERVANT' WHO STRUCK SWEETHEART DEALS WITH GIANTS, FLEW BUSINESS CLASS ON THE TAXPAYER AND LEFT HIS £165,000-A-YEAR POST TO WORK FOR ACCOUNTANCY FIRM THAT HELPS PEOPLE AVOID TAX HMRC head: Two of Mr Blair's advisers allege Dave Hartnett (pictrured) was approached about the trust by a consultant hired by Mr Blair’s lawyers Dave Harnett was one of the Government's most highly paid officials, with a £165,000-a-year salary as head of HMRC - and perks to match. Mr Hartnett left his post in 2012 with a year's salary, £48,000 in unclaimed holiday and with a pension pot worth £1.7million - £80,000 a year. During his tenure, he met the biggest names in business and went on to work for Deloitte - after meeting senior British partner David Cruickshank 48 times between 2007 and 2011. The salary for the one-day-a-week post at one of the world's top accountancy firms was never disclosed, but it no doubt came with all the perks enjoyed by staff in the lucrative industry. However, Mr Hartnett hardly suffered under HMRC, enjoying the sort of pay and expenses that would lead to national scandal if the Prime Minister allowed himself the same indulgences. In 2010, Mr Hatnett enjoyed a £6,000 trip to the Mumbai International Taxation Conference, flying business class and staying in £200-a-night hotels on the taxpayer. Mr Hartnett’s tenure at HMRC, which ended in July 2012, was dogged by claims that he helped multinational companies shave millions of pounds off their tax bills. He was severely criticised for brokering a deal that saved Goldman Sachs £20million in interest payments. The deal was described by a judge last month as lawful, but ‘not a glorious episode in the history of the Revenue’. On another occasion, Mr Hartnett allowed Vodafone – a Deloitte client – to pay £1.25billion of an alleged £6billion tax bill – figures which are disputed by the telecoms company. After being accused of lying to MPs last year, Mr Hartnett left HMRC and joined HSBC as an adviser on honesty. In 2013, he accepted a one-day-a-week post with Deloitte – the firm that signed off the accounts for coffee chain Starbucks which, entirely legally, paid no corporation tax for three years by channelling its revenues through Luxembourg and Switzerland. During his time as HMRC boss, Mr Hartnett met Deloitte’s senior British partner David Cruickshank 48 times between 2007 and 2011, including meetings about Vodafone. Advertisement

The advisers told undercover reporters that Mr Blair had used the interest-in-possession (IPP) trust to receive payments from his consultancy work, some of which was with controversial regimes.

IIP trusts are legal entities that can hold property, shares or other sources of income for a beneficiary, most commonly for their lifetime.

According to experts, such trusts can offer significant tax advantages, including the possibility of passing on wealth to children free of tax.

Demands: Conservative MP David Davis wants an inquiry into HMRC giving preferential treatment to high-profile individuals

The trusts do not have to file accounts. Lawyers for Mr Blair said the trust had been set up due to a desire for privacy. They stressed he did not seek or obtain a tax advantage.

But the fact of its existence raised questions about whether Mr Blair received special treatment due to his position, which is why MPs are now demanding an investigation.

The Times was not able to verify independently that the HMRC chief was contacted in the way the two advisers separately claimed.

Mr Blair’s representatives said Mr Hartnett had not been consulted on his behalf and no special treatment had been sought or received.

Mr Hartnett has previously been criticised for offering ‘sweetheart’ deals to companies including Goldman Sachs and Vodafone during his time as head of HMRC.

There is no suggestion that he offered such a deal to Mr Blair.

Mr Hartnett, who left HMRC four years ago, said last night he had ‘no recollection’ of the advisers’ claims. He added: ‘I don’t give advice to individuals at all.’

A spokesman for the former PM said: ‘Tony Blair did not set up this structure for reasons of tax advantage.

‘He has paid full UK tax on all his earnings. He specifically instructed the accountants who set up the structure that there was to be no tax advantage or avoidance through it.

‘Neither did he receive any special privilege from the tax authorities. So the entire premise of the story is mistaken as we have repeatedly told the Times for the last year.’