Under the 1947 UN 'headquarters agreement', the US is required to allow access to foreign diplomats but Washington alleges that it can deny visas for 'security, terrorism and foreign policy reasons'.
The demonstrators protested near the US embassy carrying posters of Suleimani and Iranian Supreme Leader Ayatollah Ali Khamenei and raised slogans of 'Down with America and Israel'.
The industry believes that this could not only result in a spike in airfares especially for passengers bound for Europe and US and but also burn a hole in the airlines’ coffers.
Iran's ambassador to the United Nations, Majid Takht Ravanchi, told CNN that the killing was an 'act of war on the part of the United States'.
Although the United States and Iran have long been adversaries and engaged in a shadow war in the Middle East and elsewhere, the US has never declared formal war on Iran.
The Friday strike that killed the most prominent Iranian general may have ended any chance that he would get the United States out of the 'endless wars' in the Middle East that he has railed against.
General Soleimani, the head of Iran's elite al-Quds force and architect of its regional security apparatus, was killed following a US airstrike at Baghdad's international airport.
For the US and Israel, he was a shadowy figure in command of Iran's proxy forces, responsible for fighters in Syria backing President Bashar Assad and for the deaths of American troops in Iraq.