TEHRAN, Jan. 4 (Xinhua) -- Iranian Parliament Speaker Ali Larijani said Tuesday that Iran plans to further boost its missile power to defend itself against the potential threats of the U.S. and Israel, the semi-official Fars news agency reported.

"We do not conceal the fact that we seek to boost the power of our missile systems," Larijani was quoted as saying.

"As long as the U.S. and the Zionist regime threaten us, we will work on our missile systems which are used for defensive purposes," he added, according to the report.

Larijani also dismissed the U.S. and Israel's alleged concerns about Iran's missile program, and said the country has produced short and medium-range missiles merely to defend itself against possible aggressions, said Fars.

Aerospace Commander of the Islamic Revolution Guards Corps (IRGC) Amir Ali Hadgizadeh told Fars news agency on Sunday that Iran had shot down many western drones, two of them in Persian Gulf.

Iran has made considerable progress in the past decades over the development of the medium and long-range missiles, however, Teheran has reiterated that its missile capability is "a defensive tool against invasions."