South Korean researchers warn North Korea is building new missile bases at home, while it seeks help from Iran to improve and market its long-range missile technology.

The Institute for Foreign Affairs and National Security in Seoul says despite severe poverty and hunger, North Korea remains very much in the missile development business.

Picture from file video of unidentified North Korean missile launch

In a new report, the institute says Pyongyang is building clusters of new missile bases along its eastern coast, and there are about 250 missiles on the bases that could target Japan and the U.S. forces there. It also says the North is building a command center to coordinate mobile launch pads for short-range missiles aimed at South Korea.

The institute is funded by the South Korean Foreign Ministry and is a center for training diplomats and developing foreign policy.

North and South Korea remain technically at war, after an armistice halted fighting between them in 1953. The United States stations about 25,000 troops in South Korea to deter Pyongyang from repeating its 1950 invasion of the South.

There are more than 50,000 U.S. troops in Japan.

The new report says Pyongyang is cooperating closely with Iran to improve its long-range missile capabilities. Choi Jong-chol, with South Korea's National Defense University, says there is a natural link between the two countries.

Choi says Iran has plenty of oil wealth it can use to spend on advanced missile research from North Korea. He says both have been labeled "rogue" countries by the international community, and have a common interest in teaming up against the United States and its allies.

The institute's report says more than just money flows from Iran to North Korea. It says Pyongyang probably benefits from Iran's weapons research, because of Tehran's arms trade with China. Iran also may have helped North Korea get nuclear weapons technology from Pakistan. The man who lead Pakistan's nuclear weapons program has admitted illegally transferring some nuclear technology to Pyongyang.

The report echoes Washington's suspicion Iran may play a role in helping North Korea sell missiles and missile technology to terrorist groups.

On July 5, North Korea tested seven missiles, including a long-range Taepodong 2, which failed shortly after launch. The tests defied warnings from South Korea, the United States and Japan that launches would further isolate the impoverished communist state.

Those launches, along with North Korea's refusal to return to talks aimed at ending its nuclear weapons capabilities, have caused alarm worldwide.

South Korea responded to the launches by suspending food aid to the North - a departure from its usual policy of engagement with Pyongyang.

Jung Sung-chang, a security analyst at the Sejong Institute here in Seoul, says North Korea's military activities are its only international leverage.

Jung says North Korea is far outpaced by South Korea and other countries in almost every indicator of national strength. Military tools, he says, are the only way Pyongyang knows how to seek diplomatic, political, and economic gains.