The claim was made by former Iraqi National Intelligence Service spokesman Saad al-Alusi less than a week before Iraq's general election, in which allegations of vote buying and exorbitant hand-outs have become widespread.
Mr Maliki, who faces a bitterly contested final week of campaigning before the March 7 poll, has been photographed handing out guns, engraved with a personal message from his office, to supporters in southern Iraq. But he denies the delivery of weapons, and cash payments, were improper.
Mr Alusi, who was the intelligence spokesman until eight days ago, said 8000 guns were ordered from a Serbian supplier at the end of 2008 for use by intelligence officers. But he claimed Mr Maliki ''denied our contract at the last minute and made his own contract of 10,000 pistols, which he has used as election propaganda for himself and his party''.
''This was a very important contract for the intelligence service. We have no weapons to this day,'' Mr Alusi said.
Government spokesman Ali al-Dabbagh said: ''These gifts have been given to the tribes for their contribution to security. They are not connected to the election campaign. The suggestion that anything has been taken away from other bodies to use for election purposes is wrong.''
Tensions between Mr Maliki's office and the intellgence service had been bubbling throughout last year, before boiling over in August when its director Muhammad al-Shahwani was sacked by Mr Maliki's senior staff. Mr Alusi said about 190 employees had been sacked in recent weeks.
The head of Iraq's parliamentary integrity commission, Sheikh Sabah al-Sayedi, confirmed that guns had been handed out to community leaders and said his commission would ask Mr Maliki to account for money he allegedly used from government coffers for his re-election campaign.