Belligerent threats against Iran began to increase from the beginning of this year against a backdrop of conflicting reports on the Iranian nuclear programme. The Vienna-based International Atomic Energy Agency (IAEA), an agency of the United Nations (UN), issued a report in November 2011 which raised suspicions about the possibility that Iranian nuclear programme sites are being used for military purposes. Around the same time, US government sources said Iran was far from obtaining a nuclear weapon and that economic sanctions against Iran had been effective. Meanwhile, there was an escalation in Israeli threats against Iran, along with reports that the Zionist state had obtained weaponry capable of penetrating several metres of concrete, making capable of striking fortified underground sites.