The United States’ Ambassador to the United Nations, Kelly Craft, said on Thursday that Washington was now “ready to engage without preconditions in serious negotiations with Iran”. In a letter to the UN, the US justified the killing of Iranian General Qasem Soleimani as an act of self-defence. Iran has retaliated by firing missiles at air bases housing US forces in Iraq causing no casualties. It also told the UN it was an act of self-defence. Gen Soleimani was widely held as being Iran’s second most senior official. As head of the Revolutionary Guards’ elite Quds Force, he was an architect of Iranian policy in the region. In a letter to the UN Security Council, US Ambassador to the UN Kelly Craft said the US was ready to negotiate “with the goal of preventing further endangerment of international peace and security or escalation by the Iranian regime”. The killing of Soleimani was justified, the letter argued, under Article 51 of the UN Charter, which requires states to “immediately report” to the Security Council any measures taken in exercising the right of self-defence. She said the aim was to deter Iran from conducting or supporting attacks and degrade its ability to conduct attacks. Iran had retaliated on Wednesday for Soleimani’s death by firing missiles at military facilities housing US troops in Iraq. President Donald Trump said no Americans were hurt, soothing fears that Soleimani’s death and the Iranian response could spark a wider conflict in the Middle East.