Former ambassadors, senior military figures and a bishop were among 44 signatories of an open letter to Prime Minister Tony Blair calling for an inquiry into civilian deaths in Iraq.

The former Assistant Chief of Defence Staff Lord Garden put his name to the appeal, alongside retired General Sir Hugh Beach, ex-ambassador to Iraq Sir Stephen Egerton and the Bishop of Coventry, Colin Bennetts.

The letter follows a study published in The Lancet in October which estimated the number of excess deaths in Iraq since the outbreak of hostilities in March last year at 98,000.

The study, by a team of American and Iraqi researchers, said most of the additional deaths were women and children, and said the risk of violent death was higher after the war than before.

The letter urged Mr Blair to set up an independent inquiry to establish with the greatest possible accuracy the number of people killed or injured in Iraq, along with the reason for the casualties.

While rejecting the Lancet figures, the Government has offered no estimate of its own of the number of deaths resulting from the war and occupation, the signatories noted.

The publication of the letter marked the launch of a new joint campaign www.countthecasualties.org.uk by health charity Medact and the Iraq Body Count project, who are challenging the Government to count casualties systematically, rather than simply rejecting independent assessments as "unreliable".

Other signatories to the letter included the secretary general of the Muslim Council of Britain Iqbal Sacranie, human rights campaigner Bianca Jagger, writer Harold Pinter and former ambassadors Oliver Miles, Robin Kealy, Sir Brian Barder, Sir David Ratford.

A number of eminent health professionals and academics have also signed it.

Foreign Secretary Jack Straw last month told the House of Commons that the Government believed the most accurate data came from the Iraqi Ministry of Health, which estimated that 3,853 civilians were killed and 15,517 injured between April and October 2004.