In April 2008, the British government expressed increasing concern over US Air Force reconnaisance flights from RAF Akrotiti in Cyprus using U-2/TR1 "spy" aircraft. These aircraft collect imagery and also use the large pods under each wing to collect short-range sigint. They are based permanently at the RAF station but require UK permission to fly. Hitherto, this permission had been arranged through military to military links. Now the UK requested a much more detailed and cumbersome process involving the Foreign Office.
The U2 aircraft were employed in "Operation Cedar Sweep" to fly surveillance against Hezbollah militants, with the resulting intelligence being provided to the Lebanese government. The U2 aircraft were also used in "Operation Highland Warrior" to fly missions over Turkey and northern Iraq to collect intelligence against the PKK which was then passed to the Turkish government. The use that the intelligence was put by these third parties was a matter of growing concern.
The concerns of the British were the result of the activities of the European Court of Human Rights and the Council of Europe. The Vienna Commission recently asserted that the European Convention lays a legal duty upon member states to regulate the activities of allied intelligence services within their territory - or launched from their territory. The UK govenrment was anxious that use of the intelligence collected by the American U2s could lead to the UK being accused of being complicit in the torture or killing of suspects. London was also worried that any controversy could jeopardise the position of the soveriegn bases on Cyprus, including the large sigint ground station at Ayios Nikolaos, which the Foreign Office asserted was absolutely vital to UK national interests.