Iran President Hassan Rouhani has said, the problems of the world will not be overcome if countries do not agree with the principles of ethics and morality in foreign policy. <br/><br/>Giving a speech at a lecture organised by Observor Research Foundation in New Delhi Saturday evening, Mr Rouhani said, unpleasant issues in the world such as aggression and violence arise from miscalculations on part of states. <br/><br/>He said, ethics will have to be superior to national interests to have permanent security and peace. <br/><br/>The Iran President said, politicians and world rulers must act and negotiate with the world within the framework of reason and ethics.