Pakistan Army chief Field Marshal Asim Munir spoke with US President Donald Trump last week, days before his planned visit to Tehran, according to three Pakistani sources cited by Reuters.The previously unreported call came as Washington prepared to impose major economic sanctions targeting Iran and countries that trade with Tehran. It remains unclear what Munir and Trump discussed.Munir is scheduled to travel to Tehran on Monday for talks with Iranian leaders as Islamabad steps up efforts to revive stalled negotiations between Washington and Tehran.Iran’s foreign ministry announced Munir’s visit on Sunday, saying he would discuss bilateral relations and regional issues with Iranian officials.He will be accompanied by a delegation expected to hold high-level meetings with the Iranian leadership.The visit comes as Pakistan seeks to revive diplomatic efforts between the United States and Iran after an interim agreement aimed at creating a 60-day window for high-level peace talks broke down last month.Pakistan had signed the agreement as a guarantor and has since been trying to bring Washington and Tehran back to the negotiating table.Pakistan has increased its diplomatic engagement with Iran in recent weeks. Pakistan interior minister Mohsin Naqvi travelled to Tehran earlier this month and met Iranian President Masoud Pezeshkian and Foreign Minister Abbas Araghchi.Iranian Foreign Ministry spokesperson Esmaeil Baghaei said on Sunday that Munir’s visit would focus on strengthening bilateral cooperation and supporting efforts to promote peace and security in the region.The Pakistani government has not officially commented on Munir’s reported conversation with Trump.The reported Trump-Munir call comes as Washington steps up pressure on Tehran.Trump warned on August 20 that the United States would launch what he called the “most crushing economic operation” against Iran if Tehran failed to reach a deal.Pezeshkian on Sunday defended the June agreement, describing it as the best way for Iran to move beyond a situation of “neither war nor peace”.At the same time, Mohsen Rezaei, Iran’s new hard-line head of the Supreme National Security Council, warned neighbouring countries against joining any renewed US campaign targeting Iran’s economy.The earlier negotiations collapsed after tensions between Washington and Tehran escalated in mid-July, following renewed military strikes.Pakistan’s mediation efforts have so far failed to produce a breakthrough, with the Strait of Hormuz remaining a major obstacle amid disruptions to one of the world’s most important energy shipping routes.