<span style="color: #222222;">Iran President Hassan Rouhani has warned western countries that they will face a massive influx of drugs if his country becomes weakened by US sanctions. He was speaking today at a six-nation conference in Tehran on fighting terrorism. </span><br />'' <br />'' <span style="color: #222222;">Parliament speakers of Afghanistan, Iran, Pakistan, Turkey, China and Russia attended the conference. In remarks broadcast on state TV, Mr Rouhani said, a weakened Iran would be less able to fight drug trafficking. </span><br />'' <br />'' <span style="color: #222222;">Iran lies on a major drug route between Afghanistan and Europe and the Persian Gulf states. Afghanistan is the world's largest producer of opium with its Helmand Province being the biggest opium-producing region.  </span><br />'' <br />'' <span style="color: #222222;">Iran's economy is reeling after the US re-imposed sanctions lifted under Tehran's nuclear deal with world powers. President Donald Trump withdrew the US from the deal and began restoring sanctions. Mr Rouhani called the US sanctions as economic terrorism. </span>