The International Atomic Energy Agency has expressed concern over Iran's decision to begin higher enrichment of uranium from today. Iran formally informed the agency about the decision through a letter yesterday.The IAEA Chief Yukiya Amano said in Vienna that the decision would affect the ongoing international efforts to ensure the availability of nuclear fuel for Tehran's Research Reactor.<br/><br/>Meanwhile, the United Sates and France have said they will push for strong new UN sanctions against Iran after its announcement to step up its uranium enrichment. French President Nicolas Sarkozy and US Defence Secretary Robert Gates agreed during talks in Paris that tough new sanctions must be passed against Iran to compel it to resume dialogue. Other countries including Germany, Britain, Russia, and Australia have also expressed their concerns about Tehran's decision.