ERBIL, Kurdistan Region of Iraq - Iran's Islamic Revolutionary Guard Corps (IRGC) on Thursday warned the US and Israel "to avoid any miscalculations" as the funeral ceremony for the country's late supreme leader nears, with negotiations between Washington and Tehran pegged to continue following the decorous send-off.

On February 28, Ali Khamenei, Iran’s long-ruling supreme leader, 86, from Mashhad, was killed in a US-Israeli strike on his compound in Tehran. He served as Iran’s highest political and religious authority for nearly 37 years, making him the country’s longest-serving leader since the 1979 Islamic Revolution.

Khamenei's body is set to lie in state at Tehran's Imam Khomeini Mosque on Saturday and Sunday, followed by funeral ceremonies in the Iranian capital and the religiously signifcant Qom on Monday and Tuesday, respectively.

Additionally, arrangements have been made for ceremonies to be held within Iraq's Karbala and Najaf, the two holiest cities in Shiite Islam. The late Iranian leader is then to be buried in his hometown of Mashhad on Thursday, July 9.

The IRGC's Khatam al-Anbiya Central Headquarters, in a statement encouraging mourners to attend the proceedings in great numbers, said that Khamenei's faith in the armed forces during his tenure brought the Islamic Republic's "deterrent power to its peak," causing the US and Israeli to experience "the taste of humiliation" during the recent regional conflict.

"We warn the enemies of strong Iran, especially America, the Zionist regime, and their regional and extra-regional accomplices, to avoid any calculation errors and to think about the harsh and regretful reactions of the children of the Iranian nation in the armed forces, to any threat and aggression in the area of ​​our beloved country," the IRGC continued.

Iranian Parliament Speaker and chief negotiator Mohammad Bagher Ghalibaf echoed the calls for large attendance, saying that the farewell ceremonies will serve as an "undeniable document of the steadfastness of the Iranian nation."

"We must rise up and carry the nation's cry for retribution to the world, so the world knows that the noble and honorable nation of Iran will not stay silent in the face of oppression and arrogance," said Ghalibaf.

US-Iran negotiations, which have tenuously proceeded after both sides signed a Memorandum of Understanding (MoU) on June 17 agreeing to end all hostilities, continued in an indirect formate in Doha in recent days, with US President Donald Trump asserting that the respective delegations have been "getting along very well."

Majed Al Ansari, the spokesperson for Qatar's foreign ministry, on Thursday said that "positive progress" was made during the talks, which were mediated by Qatari and Pakistani diplomats.

He noted that both sides have agreed to continue the negotiating process and that the next round of talks will be scheduled "at the earliest possible time following the funeral processions of the former Iranian Supreme Leader." 

Iranian Foreign Minister Abbas Araghchi recently visited Karbala and Najaf ahead of the transfer of Khamenei's body for funeral proceedings, with the top diplomat asserting that the service "will undoubtedly be remembered by history and further strengthen the bonds between our two nations."