Tory leader David Cameron has told his frontbenchers to declare details of any family members who work for them in the wake of the Derek Conway scandal.

Mr Cameron said shadow ministers would also include details of how much they paid family members working for them.

He said the move was one of a number of measures he was introducing to increase "transparency and accountability" with MPs' expenses.

Mr Conway's case was suspended from the House for ten days after paying his sons tens of thousands of pounds for little or no work.

His case has provoked a flurry of efforts by party leaders to improve the transparency of the system and persuade MPs to declare if they employed family members.

Almost 180 have since confirmed that they do - more than a quarter of the Commons.

Downing Street said that Gordon Brown had spoken with Commons Speaker Michael Martin about the "root and branch" review of MPs' expenses to be carried out by the Members Estimate Committee.

Mr Brown's spokesman said: "He believes that there must be greater transparency all round in future, including in relation to MPs' expenses".

Mr Cameron has produced a declaration form on which all of his frontbench team will be required to set out who they employ at taxpayers' expense, whether they are family members and exactly how office and housing allowances were spent.

The new scheme was discussed by the Shadow Cabinet ahead of meetings between Mr Cameron and senior backbenchers and then all of the parliamentary party.

He conceded that not all of his MPs were "overly enthusiastic" about the idea but the general view was that action was needed and that many would be willing to voluntarily supply the information.

The first declaration will come in July, for the second quarter of this year, with the forms then returned annually each April and the results published centrally for scrutiny.

Mr Cameron said: "This is not the last word on this. I am sure this can be improved and amended.

"But the aim is to find a simple and transparent form that demonstrates where this money actually goes."

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