TEHRAN - Iran has cut links with the British Museum over its failure to lend the Islamic Republic an ancient Persian treasure, Iranian media reported on Saturday, in the latest sign of worsening relations between the two countries. Iran's Cultural Heritage Organisation said in October it had set a two-month deadline for the British Museum to allow the public display in Iran of the so-called Cyrus Cylinder, linked to the Persian ruler's 6th century BC conquest of Babylon. The museum, which houses a vast collection of world art and artefacts, said in September that plans to hand over the 2,500-year-old clay cylinder had been delayed due to unspecified "practicalities". Hamid Baqaie, head of the state Cultural Heritage Organisation, said the museum had failed to meet the deadline, ISNA news agency reported. He said it had offered to deliver the cylinder by July instead but that this was not acceptable. "The Cultural Heritage Organisation has cut all its relations and cooperation with the British Museum," he said, adding the move concerned archeological, exhibition and research cooperation. Iran is already at odds with Britain and other Western powers over the Islamic Republic's nuclear energy programme, which the West suspects is for military aims. Iran denies this, saying it aims solely to produce electricity.