An MEP for the United Kingdom Independence party is being investigated by the European Union’s anti-fraud watchdog over his use of expenses.

Michael Nattrass, who has represented the West Midlands in the European parliament since 2004, is the subject of an inquiry into whether Denis Brookes, one of his former aides, was paid through public funds while he was working as a regional organiser for UKIP. The EU does not allow taxpayers’ money to be used to pay party officials.

The inquiry into Nattrass, which is part of a wider investigation into UKIP’s finances, comes as one of its former MEPs, Tom Wise, was jailed last week for two years for embezzling funds out of his assistant’s allowance.

Separately, it has also emerged that Nattrass was using a business of which he was an equity partner as the “paying agent” for all his assistants’ salaries provided by the EU.

Between 2004 and summer this year, all of his assistants’ allowances were channelled through the business account of Nattrass Giles, a chartered surveyors in Birmingham which he founded nearly 30 years ago.

Nattrass was a signatory to the bank account, although he insisted last night that the administration was handled by another partner in the firm who has since died.

MEPs must not act as their own paying agents. The role can only be performed by “third parties”.

New rules brought in since July this year have further tightened the controls and MEPs can now only use accredited people or companies as paying agents.

Nattrass said he had been told by EU officials that he could use his Birmingham company.

He also insisted that Brookes had worked for him in his capacity as an MEP until his employment as an aide came to an end three years ago.

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