Talks between Iran and the United States are facing a critical moment as the temporary ceasefire approaches its expiration on April 22, amid Iran’s closure of the Strait of Hormuz and rising tensions. As President Donald Trump and Iran’s Supreme National Security Council review responses to new proposals delivered through the Pakistani mediator, Israel and U.S. officials warn of the possibility of renewed conflict and military strikes if no agreement is reached on nuclear issues and the maritime shipping corridor.

Tensions in the Strait of Hormuz escalated again yesterday after Iran reversed its decision to reopen the vital waterway and fired on ships attempting to cross it, saying the move was “a response to the United States’ continued blockade of Iranian ports.” The Islamic Revolutionary Guard Corps declared that the strait would remain closed until the U.S. blockade is lifted, warning that “no ship should move from its anchorage, and any attempt to approach the Strait of Hormuz will be targeted.”

Meanwhile, Pakistan’s army chief, Asim Munir, left Tehran, apparently carrying Iran’s response to the U.S. offer and Washington’s conditions. This comes after Iran’s Supreme National Security Council confirmed that Munir had conveyed new proposals. In a statement yesterday, the council said Tehran “is reviewing the new U.S. proposals and has not yet responded.”

However, it stressed that “the Iranian negotiating team will not make any concessions, will not retreat, and will not show leniency on any issue, and will defend the interests of the Iranian nation with all its strength.”