POLITICIANS will have to promise never to lie while in office, The Times has learnt.

For the first time MPs, ministers and civil servants will have to agree to a code of conduct which binds them to the truth as part of a package of measures proposed to combat the low level of public trust in Government. Sir Alistair Graham, head of the powerful sleaze watchdog, is driving through the first major changes to the Seven Principles of Public Life since their introduction in 1995.

The chairman of the Committee on Standards in Public Life said that he believed that trust in Government had declined further over the last two years. He will start by proposing overhauling the code’s definition of “honesty” — at present a technical definition focusing on conflicts of interest — after focus groups said this missed the central point.

The final wording of the new definition has yet to be agreed, but Sir Alistair said that it must revolve around the notion of truth. At present, MPs are prohibited from lying in the House of Commons, but there is no specific stipulation that they must tell the truth outside the chamber.

In an interview with The Times, Sir Alistair said: “We have had a research organisation doing focus group work, and it was clear that some of the language of the descriptors did not resonate with the public. The public have told us it should be about the truth. That’s what they want from their senior politicians — to tell it as it is and own up to mistakes."

Times Recommends

• An officer and a gentle woman
• Dame Helen Mirren is worthy of the Epidaurus
• Foods that can help to prevent swine flu