One of Boris Johnson’s senior advisers has had his City Hall credit card revoked after he was discovered buying personal items on the public purse.

Ian Clements, a deputy mayor to Mr Johnson, has been disciplined following an internal investigation.

He used the card to buy items including groceries, with the total spend amounting to about £1,000 during the past 12 months.

Although Mr Clements repaid the money, he was reprimanded by the Mayor of London because using a corporate credit card for personal use is a breach of the Greater London Authority’s regulations.

The incident is embarrassing to Mr Johnson as he has set out to establish his regime as being scrupulous when it comes to public money.

Mr Johnson, the former MP for Henley, escaped relatively unscathed from the expenses furore when his MP claims were revealed this week, although he apologised for trying to claim £16.50 for a Remembrance Day wreath.

It is understood that Mr Clements, the former leader of Bexley Council, will not be sacked because he had paid the money back before the impropriety was noticed by a GLA official.

Mr Johnson said: “Openness, transparency and taxpayer value are at the heart of my administration. I take very seriously indeed any behaviour that could potentially raise questions about that firm commitment.” A spokesperson for the mayor said that the expenditure was repaid on every occasion at “the earliest opportunity”.

John Biggs, Labour’s deputy leader on the London Assembly, called for a review of the use of City Hall credit cards. He said the Assembly’s audit committee should investigate their use by mayoral staff.

He said: “In the interests of transparency, the Mayor should release copies of the receipts for expenditure, the repayments made, and any other correspondence in the matter. In the current climate this is a fair matter for public scrutiny. I assume he didn’t buy a duck island but it is reasonable to know.”

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