[Geo News] US Senator and Chairman US Senate Committee on Foreign Affairs John Kerry said that drone attacks on tribal areas in Pakistan was a complex issue. But added that a careful approach was being adopted in this connection. He expressed concerns over enforcement of Nizam-e-Adl Regulation in Malakand, saying he doesn't have much information about the regulation. "I firmly believe that US economic aid will be provided to Pakistan," he said. Senator Kerry hoped that President Asif Ali Zardari would continue to perform his responsibilities in a better way.