US President Donald Trump has sought changes to a proposed agreement aimed at ending the war with Iran, sending a revised framework back for Tehran's consideration and potentially delaying a final deal, The New York Times reported on Saturday, citing officials familiar with the negotiations. According to the report, Trump pushed for tougher terms in the proposed agreement, although the exact nature of the changes was not immediately clear. The revised framework has been returned to Iran for review as negotiators continue efforts to reach a settlement. Separately, Axios reported that Trump wanted to reinforce several provisions he considers critical, including measures related to Iran's nuclear material. The changes could extend negotiations by several days before a decision is made on whether the agreement can bring an end to the conflict. The proposed deal had been awaiting Trump's approval, US sources previously told AFP. However, the president did not sign off on the agreement following a White House Situation Room meeting on Friday. Trump has repeatedly outlined key conditions for any agreement with Tehran, including a commitment that Iran will never develop nuclear weapons and the reopening of the Strait of Hormuz, a vital shipping lane through which roughly 20% of global oil supplies pass. The war began after the United States and Israel launched joint strikes on Iran on February 28. Since then, diplomatic efforts have sought to secure a negotiated settlement, though a final agreement has remained elusive amid competing demands from both sides.