The announced range places Israel within striking distance of the missiles.
Iran already possesses the Shahab 3D missile, which has a reported range of 2,200 kilometers. Some experts believe that the country also has versions of the North Korean Taepodong missile, based on liquid fuel, which can reach western Europe.
Mohammad-Najjar was addressing residents of Bandar Abbas, in southern Iran, the Islamic Republic News Agency reported. His speech formed part of a number of events, including an address by President Mahmoud Ahmadinejad, to mark celebrations of the anniversary of the Islamic revolution in 1979.
"Although we cannot announce all our achievements due to security reasons and preventing misuse of enemies, production of different anti-armor and surface-to-surface missiles with warheads and a range of 2,000 km are just parts of our defense capabilities," Mohammad-Najjar said.
The Iranian defense minister added that voluntaries in Iran's armed forces are "more valuable for the country than atomic bombs."
Meanwhile, senior Iranian nuclear negotiator Ali Larijani claimed his country posed no threat to Israel during a security conference in Germany.
"That Iran is willing to threaten Israel is wrong," Larijani said. "We pose no threat and if we are conducting nuclear research and development we are no threat to Israel. We have no intention of aggression against any country," he said.
'Iran producing drones invisible to radar'
In an apparent deferment of another escalation with the West, Ahmadinejad chose to allow senior security officials to deliver promised announcements on Iran's new military capabilities, while the Iranian president himself merely vowed further news on the country's nuclear program.
"From now until April 9 you will hear frequently about the great progress of the Iranian people and unique developments in the domains of industry, agriculture, and especially nuclear energy," he told a mass rally in Tehran.
Ahamadinejad also asked rhetorical questions underlining Iran's unwillingness to comply with international demands to halt its uranium enrichment progress.
"If you are willing to negotiate why do you insist on a suspension (of nuclear enrichment)?' he asked, adding: "If we suspend our activities then what are we going to talk about? Why if your nuclear plants are working 24 hours a day why must Iran be pressured to shut them down?"
Earlier, the Commander of the Islamic Revolution Guards, Major General Yahya Rahim Safavi, announced that Iran had begun mass producing drones invisible to radar.
According to Safavi, whose statement was reported by the Islamic Republic News Agency (IRNA), the new drone will have "a range of 700 kilometers."
"The drone can be used in reconnaissance operations, information gathering, picture dispatching and film shooting," the general said, adding that "the shape and material of the drone makes it impossible to be detected by radars so it cannot be targeted."
"The drone has passed its experimental phase and is being mass produced, and we are currently using it in our operations," Safavi claimed.
He added that the drone was a defensive tool, saying: "We do not intend to invade countries and we do not believe in expansionism, rather, we are to protect our revolution, develop our country and remove our problems."
Earlier, "huge masses of people thronged into the streets throughout the country Sunday morning to mark the 28th anniversary of the victory of the Islamic Revolution," the IRNA said.
In the past week, Iranian state information agencies have boasted a number of Iranian 'achievements,' including an alleged AIDS cure, as part a build-up of Iran's official 'ten-day dawn' celebrations marking the Islamic revolution.
The AP contributed to this report