US and Iranian negotiators reached a tentative agreement on Thursday to extend the ceasefire in the three-month-old war by 60 days and launch talks on Iran’s nuclear program, according to a US official familiar with the matter.The official, who was not authorised to comment publicly and spoke on condition of anonymity, said President Donald Trump still needs to sign off on the emerging memorandum of understanding.Iran did not immediately confirm any tentative deal with the United States.The tentative agreement worked out by the two sides comes at a moment when the fragile ceasefire between the US and Iran appeared to be wavering.The US military earlier on Thursday accused Iran of violating the ceasefire after Kuwait reported coming under attack following an American strike against the Islamic Republic. It was the latest flare-up of fighting to threaten ongoing negotiations to end the war.Details of the tentative agreement were first reported by the news outlet Axios.US Central Command said Kuwait intercepted missiles fired from Iran late on Wednesday, and military officials called the attack on one of America’s top allies in the Persian Gulf an “egregious ceasefire violation”.Kuwait had earlier announced an attack on its territory, and Iran said it had retaliated for strikes earlier in the week by firing on a US base in a Gulf state it did not name. The Kuwaiti Foreign Ministry condemned Iran for what it called “blatant aggression”.The exchange unfolded after US officials said late on Wednesday in Washington that American forces launched more strikes on Iran, shooting down four one-way attack drones that posed a threat around the Strait of Hormuz and hitting an Iranian ground-control station in Bandar Abbas that was about to launch a fifth drone.Washington and Tehran have repeatedly accused each other of violating the seven-week ceasefire and have traded strikes throughout the week. But they have not returned to full-scale hostilities and have kept negotiating. Trump has insisted he’s confident that his administration is making headway in the talks.