Labour has called for an investigation into whether Jacob Rees-Mogg broke the financial rules for MPs by failing to declare that he got £6m in cheap loans from one of his companies. The senior Tory minister and leader of the House of Commons, an ally of Boris Johnson, did not report to the official register that he received director’s loans from Saliston between 2018 and 2020. Rees-Mogg owns Saliston, even though he gave up his directorship in 2019. It has a stake in Somerset Capital Management, an investment company, the parent firm of Somerset Capital Management (Cayman) in the Cayman Islands. Accounts for Saliston show the £6m in loans – £2.94m in 2018, £2.3m the following year and £701,513 in 2019-2020 – attracted interest paid at the equivalent of about 0.8%, which is below market rates. The accounts list the loan as attracting interest rates of 2.5% and 3.5% in individual years, raising the prospect that he could have borrowed the money and repaid it over short periods of time. The MPs’ code of conduct does not specifically cover directors’ loans but it states: “Members shall fulfil conscientiously the requirements of the house in respect of the registration of interests in the register of members’ financial interests. They shall always be open and frank in drawing attention to any relevant interest in any proceeding of the house or its committees, and in any communications with ministers, members, public officials or public office holders.” Labour’s Thangam Debbonaire, the shadow leader of the Commons, said: “This would appear to be yet another egregious breach of the rules. A cabinet minister failing to declare millions of pounds of additional income is unacceptable. “The parliamentary commissioner for standards must investigate this. Jacob Rees-Mogg must come clean about all of his financial interests outside of parliament.” A spokesperson for Rees-Mogg said he stood by his statement that it had been properly declared, after the Mail on Sunday reported the story. Rees-Mogg said: “Saliston is 100% owned by me. This is declared clearly in the Commons register and to the Cabinet Office. “It has no activities that interact with government policy. The loans from 2018 were primarily taken out for the purchase and refurbishment of [my home] as temporary cashflow measures. All loans have either been repaid with interest in accordance with HMRC rules or paid as dividends and taxed accordingly. “I have no managerial responsibility for Somerset Capital Management. However, I know that the Cayman company purely provides a fund for non-UK investors but any and all money it makes returns to Somerset Capital Management in the UK where it pays full UK taxes.” Meanwhile, one of Rees-Mogg’s Conservative colleagues came under scrutiny over lobbying. The Sunday Times reported that a unit in the Department for Transport (DfT) set up by Grant Shapps, a private aviation enthusiast, had been lobbying against housebuilding on small runways. The DfT said the team was not a lobbying body and instead provided “support to general aviation on a range of matters affecting their operations”.