Iranian President Hassan Rouhani today said that assassination of Islamic Revolution Guard Corps Commander and Lieutenant General Qasem Soleimani was a big mistake by the US and called on the regional states to unite against Washington's threats. <br />'' <br />'' President Rouhani made the remarks in a telephonic conversation with his Turkish counterpart Recep Tayyip Erdogan.<br />'' <br />'' Hassan Rouhani also met Qatari Foreign Minister Mohammed bin Abdulrahman Al Thani in Tehran today. <br />'' <br />'' According to the Iranian News Agency IRNA, President Rouhani told Qatari Foreign Minister that the assassination of Qasem Soleimani will have repercussions in the region and US will pay a heavy price for its terrorist move. The President further said that Iran is not seeking tensions and regional insecurity.<br />''