Pakistan, Aug. 13 -- European countries, including the United Kingdom, France, and Germany, have sent a strong warning to Iran regarding its nuclear program, hinting at reimposing United Nations sanctions if diplomacy fails.

The letter to UN Secretary-General Antonio Guterres and the Security Council stated that the three nations are committed to using all diplomatic measures to prevent Iran from developing nuclear weapons beyond agreed limits.

The European powers threatened to activate the "snapback mechanism," a part of the 2015 nuclear deal, which allows re-imposing UN sanctions if any party violates the agreement, set to expire in October.

The warning comes after Iran suspended cooperation with the International Atomic Energy (IAEA...