THE Conservatives have lodged a formal complaint with electoral watchdogs demanding an inquiry into allegations that Gordon Brown is using a charity as a front to fund his personal political ambitions.

They allege that the Smith Institute is providing and funding polling, policy advice and media training for the chancellor. The institute has raised almost £1.7m in the past five years.

The Tories have this weekend written to the Electoral Commission calling for the institute to be forced to reveal the identities of its backers, marking a significant escalation in their attacks on Brown.

Under electoral laws, any organisation that develops policy for political parties or helps promote politicians must declare all donations of more than £5,000. The Tories have also written to the chancellor and the cabinet secretary demanding that Brown declare his links to the institute in the register of member’s interests.

Run by Wilf Stevenson, one of Brown’s oldest friends, the institute has held more than 160 events at 11 Downing Street, the chancellor’s residence, and its publications are alleged to help shape the chancellor’s policies.

The institute is understood to have been set up after Labour came to power from the surplus proceeds of the blind trust that funded Brown’s office in opposition.

It is currently the subject of a separate investigation by the Charity Commission into whether it has broken charity rules that bar political activity. According to calculations by an accountant hired by the Tories, it has received more than £1m in tax relief since 2002.

The Conservatives have compiled a dossier of evidence – seen by The Sunday Times – which they allege reveals the institute is more than the educational charity it claims to be.

Chris Grayling, shadow transport minister, said: “These allegations expose Gordon Brown’s con trick of exploiting this organisation’s charitable status for his personal political campaigning. Any donations he receives should be openly declared, not stealthily siphoned through a charity.”

It is claimed that Bob Shrum, a US political strategist who works for Bill Clinton, and a senior fellow of the institute, is providing personal polling and strategic advice to Brown. He has held at least one seminar on how to tackle the threat of David Cameron, the Tory leader.

The institute shares offices with the left-wing New Statesman magazine owned by Geoffrey Robinson, the disgraced former Treasury minister. Robinson funded Brown’s blind trust when the chancellor was in opposition and he is also a donor to the institute.

A spokesman for Brown said: “As the chancellor has made clear repeatedly, he has no formal or financial relationship with the Smith Institute whatsoever and these allegations are just part of a Tory smear campaign.”

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