"Our fast attack craft fleet is often twice as fast as their American rivals. The plan is to make them go even faster,” Fadavi told the state-run TV on Sunday night.
Referring to the US official remarks that Washington is aware of the scope of IRGC's missile tunnels and vessels along the Iranian coasts, he said, "The Americans don’t know everything about us and the things they know is what we, ourselves, have shown and wanted them to know it."
"Their unknown is twice the realm of their known," he added.
Elsewhere, Fadavi spoke of the IRGC Navy's plans to stage massive drills in the next Iranian year (starting March 21).
In recent years, Iran has made great achievements in its defense sector and attained self-sufficiency in producing essential military equipment and systems.
Iranian officials have always stressed that the country's military and arms programs serve defensive purposes and should not be perceived as a threat to any other country.