Tory MEPs will be told to demonstrate that their finances are in order by David Cameron’s City enforcer today as a survey showed that two thirds employed their wives at widely varying rates of pay.

Hugh Thomas, a former head of compliance at Deutsche Bank, will lecture the 28 Conservative MEPs on the need for consistency and transparency after a week of allegations over expenses which claimed the jobs of their Brussels leader and Chief Whip.

The Times understands that 18 of the MEPs employ their wives as secretaries or office assistants on salaries between £10,000 and £60,000.

The lowest rate is paid by Martin Callanan, MEP for the North East, whose wife works as an administrative assistant and researcher, while the upper band of £50,000 to £60,000 is earned by Carolyn, wife of the North West MEP David Sumberg. She is listed as a full-time secretary and assistant.

Mr Thomas will find that the Conservative MEPs are angry that some of the disclosures about their use of expenses have been made possible because Mr Cameron ordered the publication of more information than either Labour or the Liberal Democrats require of their MEPs.

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