ISLAMABAD (AP) — Iran has handed over its latest proposal for negotiations with the United States to mediators in Pakistan, Iran’s state-run IRNA news agency reported Friday. The U.S. and Pakistan did not immediately confirm receiving the new proposal. There was no word on what details are included in the plan submitted late Thursday, according to the report. A shaky three-week ceasefire between the U.S. and Iran appears to be still holding though both countries have traded accusations of violations. While the ceasefire has largely halted fighting in Iran, the U.S. and Iran are locked in a standoff over the Strait of Hormuz, through which a fifth of the world’s traded oil and gas passes in peacetime. A U.S. Navy blockade stopping Iran’s tankers from getting out to sea has Iran’s economy reeling. The world economy is also under pressure as Iran maintains its chokehold on the strait. U.S.…