Under a 2001 revision to the initial agreement, signed in 1979, the South is banned from developing ballistic missiles with a range of more than 300 kilometers. It also stipulates that a payload must weigh no more than 500 kilograms, apparently to prevent the development of nuclear warheads.

“Because with the current 300 km range, (our missiles) can only reach the frontlines of the North, there are limits should we have to launch an attack (in a contingency), given (the two Koreas) are still in confrontation,” Lee said in a joint interview with local and foreign media.

“In light of a joint (defense) strategy, the U.S. also has a considerable understanding of our argument. As (the U.S.) views our strategy as reasonable, I think there will be a compromise in the near future.”

The talks over the missile pact have continued since 2010, and nothing concrete has been finalized, a senior Cheong Wa Dae official said on condition of anonymity.

Lee is expected to discuss the missile issue during the bilateral summit with U.S. President Barack Obama on the sidelines of the Seoul Nuclear Security Summit to be held March 26 and 27.

The allies are said to begin full-fledged consultations on the issue of extending the range to 800 km or 1,000 km, possibly at their regular Security Policy Initiative meeting slated to take place in Washington, D.C. next month.

“We share the view that South Korea and the U.S. will craft ways to prepare against threats of North Korea’s long-range missiles, and in this regard, we are working to devise concrete measures,” a government source told the media.

“Concrete consultations (with Washington) will get underway next month over how much longer we will extend the range.”

Some experts have called for the extension of the range to put all of North Korean territory within striking range, stressing that given that Seoul-Washington ties are closer than ever, it is an opportune time to secure the country’s “missile sovereignty.”

But opponents argue the range extension could provoke neighboring countries such as China, Russia and Japan, worsen inter-Korean ties and needlessly raise regional military tension. Observers say Washington is apparently reluctant to extend the range at a time it has spearheaded the agenda of non-proliferation and arms control.

Kim Kyung-min, political science professor at Hanyang University, said that the extension is necessary as a “self-defense” measure when neighboring states have already secured considerable ballistic missile technology.

“It is not a matter of provoking the neighboring states, but a matter of self-defense. Now is the right time (to push for the range extension) considering close ties with the U.S.,” he said.

“(Seoul’s demand for the extension) is not much. The North has missiles with a range of 3-4,000 km while China has intercontinental ballistic missiles, with Japan having developed the H2A rocket whose technology can be applied to develop ICBMs.”

With the ballistic missile ban, Seoul has instead focused on cruise missiles such as Hyunmoo-3C missiles with a range of 1,500 km. But cruise missiles are less powerful than ballistic ones and easily intercepted due to their slow speed.

Yang Uk, a senior research fellow at Korea Defense and Security Forum, said that in modern warfare, missile capabilities are the “centerpiece of a country’s defense sovereignty.”

“Beyond political, diplomatic logic, what is crucial is to secure adequate missile technology, which is more important than getting combat fighter jets. We should also think we can no longer depend wholly on the U.S. as we will retake wartime operational control from Washington (in December 2015),” he said.

“A missile is the most effective warfare tool that can be used from any spot -- on submarines, ships or land-based sites -- while inflicting the greatest damage on the hostile side and minimizing casualties of friendly forces. But we are lagging behind the North in terms of missile technology.”

Some experts, however, argue that the two allies should be careful about missile range as the extension could undermine peace and security in the region.

“When such talks (over the missile range) proceed amid good inter-Korean relations and low tension on the Korean Peninsula, it would be relatively easier to get support from the neighboring nations. But under the current situation, we should take more caution,” Professor Yang Moo-jin of the University of North Korean Studies in Seoul said.

“It is in fact unrealistic. We appear to be going backward. When we are in an era of arms reduction, we now talk about (the extension of the range), which could lead to a regional arms race.”

Seoul signed the first missile pact with Washington in 1979 despite the range limit of 180 km on condition of the U.S. assistance in missile technology development.

After years-long negotiations with the U.S. amid the North’s push for the development of advanced missile technology, the two allies agreed in 2001 to revise the original pact to extend the range to 300 km.

That year, Seoul also joined the Missile Control Technology Regime, becoming the 33rd official member of the U.S.-led program. The U.S. established the MCTR in 1987 to restrict the export of delivery systems and related technology.

The longest-range North Korean missile under development is the Taepodong-2 missile, presumed to have a range of more than 6,700 km, long enough to hit parts of Alaska, but still short of reaching the U.S. mainland.

All two test launches of the missile failed in July 2006 and in April 2009. Experts assume that Pyongyang may use and test the Taepodong-2 missile to launch what it calls a satellite next month.

The longest-range North Korean ballistic missile, deployed since 2007, is the Musudan missile with a range of 3,000-4,000 km. This missile, in theory, brings Guam, the key U.S. strategic base in the Asia-Pacific region, within its range.

By Song Sang-ho

(sshluck@heraldcorp.com)