Iran's armed forces will respond swiftly and decisively to any US interference in the Strait of Hormuz, the Khatam al-Anbiya Central Headquarters said, Jamaran reported on July 2.

Iran and the United States concluded a round of indirect talks in Doha with no sign of progress towards a lasting peace, focusing instead on issues they said had been resolved when an interim agreement was announced two weeks ago.

The Strait of Hormuz was not a playground for an aggressive United States but the sovereign territory of Iran, the headquarters said, describing the security and stability of the waterway as a red line for the armed forces.

All tanker and commercial vessels were obliged to use the route Iran had designated for safe passage through the strait, it said. Any failure to comply or deviation from the designated route, or disregard for Iran's navigation protocols, would meet an immediate and forceful response from the armed forces and endanger the security of offending vessels.

Responsibility for any attempt by the US to interfere in security matters or take disruptive action in the strait would be treated as a threat to Iran's national sovereignty and met with a swift, decisive reaction, the headquarters said.

The continued presence of US fighter aircraft, both manned and unmanned, over the Strait of Hormuz had caused insecurity in the waterway and would endanger regional security, it said.

Negotiators spent two days in Doha discussing maritime traffic in the Strait of Hormuz and the unfreezing of Iran's funds, two critical issues under the initial agreement, sources familiar with the discussions said.

The next meeting will take place after funeral processions for Iran's late Supreme Leader Ayatollah Ali Khamenei, who is due to be buried on July 9 in Mashhad, Qatar's foreign ministry said.

Iran is expected to shutdown for four days during the lengthy funeral procession of the second Iranian supreme leader, who was killed by the US and Israeli strikes on his house on February 28.

Security is also expected to be extremely tight, with fears from inside the country that the processions and events could be targets for espionage by foreign actors. Airspace above Tehran and Mashhad is expected to be fully closed during the events. 

Security is expected to be tight with leaders and top officials arriving in the Islamic Republic in a once-in-a-generation event, which is seeing a mass movement of people from the provinces to the capital and Mashhad.