Senior Iranian officials have repeatedly said that the Islamic Republic's missile programme is solely defensive in nature and is not negotiable.
In a sign of defiance, a Ghadr ballistic missile with a range of 2,000 km (1,240 miles) was put on display near the ex-U.S. embassy in Tehran, now a cultural centre, during Saturday's street demonstration, Tasnim news agency said.
"That America thinks Iran is going to put aside its military power is a childish dream," said Brigadier General Hossein Salami, deputy head of its elite Revolutionary Guards which oversees the missile development, according to Tasnim.
Fars news agency posted pictures of demonstrators nearby burning an effigy of Trump and holding up signs saying "Death to America".
Iran and the United States severed diplomatic relations soon after the 1979 revolution, during which hardline students seized the embassy and took 52 Americans hostage for 444 days.
Shamkhani spoke a few days after Khamenei said the United States was the "number one enemy" of the Islamic Republic.
U.S.-Iranian tensions have risen anew at a time when Tehran has been improving political and military ties with Russia.
Russian President Vladimir Putin visited Tehran on Wednesday. Khamenei told him that Tehran and Moscow must step up cooperation to isolate the United States and help defuse conflict in the Middle East.
Iran and Russia are both fighting on the side of Syrian President Bashar al Assad against the opposition.
