An investigation is under way amid fears that a satellite telephone registered with the British Embassy in Iraq may have fallen into the wrong hands, the Foreign Office confirmed
The telephone was barred from use in June by the company which leased it to the embassy in Baghdad after noticing discrepancies in the billing pattern.
The Foreign Office (FCO) said no-one had ever reported the telephone as missing or stolen.
But changes in the call pattern aroused suspicion and an investigation was immediately launched.
A spokesman at the FCO said they could not confirm reports in the Sunnewspaper that the telephone was stolen by insurgents who used it in Saudi Arabia and Yemen to plan terror attacks and that they ran up £500,000 worth of calls.