"It was a mistake not to include intercontinental ballistic missiles in the Iran nuclear deal," Hook said referring the 2015 Joint Comprehensive Plan of Action (JCPOA).
Hook explained in his remarks that nuclear and intercontinental ballistic missiles go hand in hand and it was insufficient to have a deal with Iran on its nuclear program that did not include ICBMs.
The official claimed that exception for intercontinental ballistic missiles in the 2015 JCPOA agreement provided Iran opportunities to develop its missile program.
According to the Fars news agency, during the event, Rouhani will also deliver a speech at a peace summit, held on the session's sidelines in commemoration of late South African anti-apartheid political leader Nelson Mandela.
The JCPOA stipulates the gradual removal of the West’s sanctions against Iran in exchange for Tehran maintaining a peaceful nature of its nuclear program.
However, US President Donald Trump announced in May the withdrawal of the United States from the JCPOA and the reinstating of the first round of sanctions in August.
The other parties to the JCPOA — Russia, China, France, Germany, the United Kingdom, the European Union and Iran — reaffirmed their commitment to the agreement.