US Army Chief of Staff Gen George Casey has met Pakistan's Chief of Army Staff Gen Ashfaq Kayani and discussed issues of cooperation in defense and war on terror, said an official statement. The meeting was held a day after the Tripartite Commission Sub-Committee s Working Group in which military experts from Afghanistan, International Security Assistance Force or ISAF and Pakistan discussed ways to enhance cooperation against improvised explosive devices and suicide incidents. The meeting would facilitate reconvening of the US-Pakistan Defense Consultative Group meeting, which was postponed some time back, an official said.