Eight people were reported killed and dozens others wounded in the attack.
Foreign Minister Manuchehr Mottaki told Iranian journalists that it was "clear" Britain played a role in the attack.
He claimed the bombers enjoyed the cooperation of British army commanders and used their facilities in the southern Iraqi city of Al-Basrah.
An unnamed British Foreign Ministry spokesman denied the accusation.
Ahvaz has been the scene of intermittent unrest by the region's Arab minority. A major bombing in the city last October killed several people and injured scores.
RFE/RL Iran Report
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