Gordon Brown was under pressure last night to explain why he has lifted a ban on ministers holding directorships as it emerged that his trade minister was listed on the board of a cleaning company, The Times can disclose.

The little noticed change to the Ministerial Code allows ministers to sit on the boards of companies while continuing their ministerial duties, something which was explicitly banned under Tony Blair.

The Conservatives say the code, which has been halved in length by Mr Brown, has been deliberately weakened. The Times has learnt that the changes are due to be examined by the sleaze watchdog, the Committee on Standards in Public Life.

According to the preface of the current document, the code provides “a helpful guide to the principles and practices of ministers”. Mr Blair’s ministers, by contrast, were required to “work within the letter and spirit of the code”.

Other changes include an end to the requirement that ministerial meetings with lobbyists should be recorded. The old code said civil servants must do this, “setting out the reasons for the meeting, and the names of those attending and the interests represented,” but this does not appear in the new code.

Lord Jones of Birmingham, the former business leader who became Minister for Trade in July, was listed yesterday in Companies House as a current director of a Worcester-based cleaning consultancy, I-Clean.

The company offers advice to corporate clients on whether cleaning contracts offer value for money, and advice on complying with health and safety legislation – an area that is overseen by Lord Jones’s department.

However, Lord Jones’s office insisted that he resigned from the company in July when he joined the Government, and I-Clean had just been slow to submit the paper. I-Clean could not be reached for comment.

A spokesman for Companies’ House said that until a director was taken off the register, he was deemed to be still in place in the eyes of the law, and it is the responsibility of directors to ensure the register is correct. Companies House public guidance says “changes of directors’ and secretaries’ details must be notified within 14 days.”

According to Companies House, Lord Jones holds three active directorship, for I-Clean Systems Limited which he held since October, Digby Jones Consulting Limited, held since September 2005 and Leicester Football Club plc, held since November 2005.

A spokesman for his office said: “Lord Jones divested himself of all paid positions on taking up his ministerial appointments. He resigned as a director of I-Clean on taking up his position as a minister. It is a matter for the company to file a form to update the registration.

“He remains a director of Digby Jones consulting. The company is privately owned by Lord Jones and his wife. It ceased to trade when Lord Jones became a minister.”

Mr Blair toughened the Ministerial Code in 1997, requiring ministers to resign any directorships on taking office and banning them from holding directorships with private companies. “This applies whether the directorship is in a public or private company and whether it carries remuneration or is honorary.”

The new code, released shortly after Mr Brown became Prime Minister, says: “Ministers must scrupulously avoid any danger of an actual or perceived conflict of interest between their ministerial position and their private financial interests. They should be guided by the general principle that they should either dispose of the interest giving rise to the conflict or take alternative steps to prevent it.”

It says that ministers should be guided by the advice from their Permanent Secretary and the independent adviser on ministers’ interests.

Chris Grayling, the Tory frontbencher, said: “Gordon Brown promised to restore trust in politics. Now the small print shows he’s actually watering down standards of ministerial accountability. This has all the hallmarks of a classic Gordon Brown con trick – short-term political advantage is allowed to override the long-term national interest.”

The Committee on Standards in Public Life is about to undertake a detailed comparison of the new and old ministerial codes, to examine what has been deleted, and whether provisions that have been removed still apply.

A committee source said: “Obviously there may be small bits that are pure repetition and no doubt they could disappear but the starting premise would be that the committee would want to see existing provisions elsewhere rather than being simply deleted, and if they were removed then there would need to be a reason for that.”

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