Pakistan’s army chief arrived Wednesday for talks in Tehran in the latest diplomatic move to ease tensions in the Middle East and arrange a second round of negotiations between the United States and Iran after almost seven weeks of war.The Pakistani military said the delegation included Field Marshal Asim Munir, the country's interior minister and other senior security officials. The group is “part of the ongoing mediation efforts,” the military said, but it gave no details.Pakistan has emerged as a key mediator in the conflict after it hosted rare direct talks between the U.S. and Iran in Islamabad, a move authorities said helped narrow differences between the two sides.Meanwhile, Pakistani Prime Minister Shehbaz Sharif arrived in Saudi Arabia on an official visit to discuss regional issues. A statement from Sharif’s office in Islamabad said he was received at the airport in Jeddah by senior Saudi officials. Sharif was accompanied by Pakistan's foreign minister and information minister.Officials say US and Iran are making progressThe U.S. blockade on Iranian ports and renewed Iranian threats strained the week-old ceasefire agreement, but regional officials said they were making progress, telling The Associated Press that the United States and Iran had an “in principle agreement” to extend it to allow for more diplomacy. They spoke on condition of anonymity to discuss the matter.But even as mediators worked for peace, tensions were still simmering. The commander of Iran’s joint military command, Ali Abdollahi, threatened to halt trade in the region if the U.S. does not lift its naval blockade.Iranian Foreign Ministry spokesman Esmail Baghaei, announcing the incoming Pakistani delegation, said Islamabad “has held discussions with the Americans and has also heard our stances. During this visit the views of both sides are to be discussed in detail.”A senior U.S. official said before the Pakistani visit was announced that the United States has not formally agreed to extend the ceasefire and that “engagement” with Iran continues. The official spoke on condition of anonymity because they were not authorized to publicly discuss the sensitive negotiations.Mediators seek compromise on sticking pointsBefore the two-week ceasefire expires on April 22, mediators are pushing for a compromise on three main sticking points that derailed direct talks last weekend — Iran’s nuclear program, the Strait of Hormuz and compensation for wartime damages, according to a regional official who spoke on condition of anonymity to discuss the mediation efforts.Baghaei said Iran is open to discussing the type and level of its uranium enrichment, but his country “based on its needs, must be able to continue enrichment,” Iran’s state media reported.The fighting has killed at least 3,000 people in Iran, more than 2,100 in Lebanon, 23 in Israel and more than a dozen in Gulf Arab states. Thirteen U.S. service members have also been killed.Trump says Iran wants a dealThe war, now in its seventh week, has jolted markets and rattled the global economy as shipping has been cut off and airstrikes have torn through military and civilian infrastructure across the region. Oil prices fell on hopes for an end to fighting on Wednesday, and U.S. stocks surged close to records set in January.Yet the future of the fragile ceasefire still hung in the balance as the U.S. pressed ahead with its blockade, which threatens to sever Iran from economic lifelines it has relied on since the war began nearly seven weeks ago, and Tehran threatened regional trade.“I think they want to make a deal very badly,” U.S. President Donald Trump said in an excerpt from an interview with Fox Business Network’s “Mornings with Maria” scheduled to air Wednesday morning. He added: “I view it as very close to over.”Trump claimed Wednesday that China has agreed not to provide weapons to Iran as reports circulated that Beijing has considered transferring arms.Trump wrote in a social media post that China is “very happy that I am permanently opening the Strait of Hormuz.” He added: “They have agreed not to send weapons to Iran.” He seemed to suggest the two are linked.China has long supported Iran’s ballistic missile program and backed it with dual-use industrial components that can be used for missile production, according to the U.S. government.US military says no ships got past blockadeU.S. Central Command said Tuesday that no ships made it past the blockade in the first 24 hours, while six merchant vessels complied with direction from U.S. forces to turn around and reenter Iranian waters.The blockade is intended to pressure Iran, which has exported millions of barrels of oil, mostly to Asia, since the war began Feb. 28. Much of it has likely been carried by so-called dark transits that evade sanctions and oversight, providing cash that’s been vital to keeping Iran running.Since the war began, Iran has curtailed maritime traffic, with most commercial vessels avoiding the waterway. Tehran's effective closure of the strait, through which a fifth of global oil transits in peacetime, has sent oil prices skyrocketing, pushing up the cost of gasoline, food and other basic goods far beyond the Middle East.Strikes continue in Lebanon after Washington talksElsewhere, Israel pressed ahead with its aerial and ground war in Lebanon. The country's National News Agency reported airstrikes and artillery shelling throughout southern Lebanon on Wednesday, including near Bint Jbeil, where Israeli forces have encircled fighters with the Lebanese militant group Hezbollah.The fighting continued after Israeli and Lebanese officials concluded their first direct talks in decades.Israeli Ambassador Yechiel Leiter said the two countries are “on the same side of the equation” in “liberating Lebanon” from Hezbollah. Lebanese Ambassador Nada Hamadeh Moawad called Tuesday's meeting “constructive” but urged an end to the fighting. Since March, that war has displaced more than 1 million people in Lebanon.Israel and Lebanon have technically been at war since Israel was established in 1948, and Lebanon remains deeply divided over diplomatic engagement with Israel.___Metz reported from Ramallah, West Bank, Ahmed from Islamabad and Corder from The Hague, Netherlands. Associated Press Writer Darlene Superville in Washington contributed to this report.