US and Iranian negotiators reached a tentative 60-day memorandum of understanding on Thursday May 28 to extend the fragile ceasefire and begin formal talks on Tehran's nuclear program, sanctions relief, and regional security. The draft includes steps to reopen the Strait of Hormuz and restore commercial shipping through the key oil-transit route. The agreement still requires final approval from President Trump and acceptance by Iran's leadership - the first concrete framework toward the durable-Hormuz-reopening invalidation leg, but unsigned and unimplemented.