Complex sentence: In principle, the UN Security Council (UNSC) and the International Atomic Energy Agency (IAEA) have confirmed Iran's right to peaceful nuclear technology under the Non-Proliferation Treaty (NPT).
Split into simpler sentences: In principle, neither the UN Security Council (UNSC) nor the International Atomic Energy Agency (IAEA) have denied Iran's right to peaceful nuclear technology. In fact, UNSC members have confirmed this right to Iran under the Non-Proliferation Treaty (NPT).