SEOUL -- Isolated North Korea claimed Tuesday that the U.S. mainland is "within the scope" of its missiles, two days after South Korea struck a deal with the United States to extend the range of its ballistic missiles.
North and South Korea have been technically at war since their 1950-53 conflict ended in a truce, not a peace treaty, and regional powers have for years been trying to rein in the North's nuclear weapons program.
North Korea is believed to be developing a long-range missile with a range of 4,160 miles or more aimed at hitting the United States, but two recent rocket tests both failed.
Its neighbors fear the North is using rocket launches to perfect technology to build a missile capable of delivering a nuclear warhead to the United States.
'U.S. imperialist aggression'
North Korea's National Defense Commission said in a statement that the North was prepared to counter any U.S. military threats, its KCNA news agency said.
"We do not hide (the fact) that the revolutionary armed forces ... including the strategic rocket forces are keeping within the scope of strike not only the bases of the puppet forces and the U.S. imperialist aggression forces' bases in the inviolable land of Korea, but also Japan, Guam and the U.S. mainland," KCNA said.
Pyongyang refuses to let failed rocket launch dampen tone of festivities.
An expert in the South expressed skepticism over the claims.
"There is no evidence that North Korea has succeeded in tests of a missile with a range long enough to hit the U.S. mainland," Yun Duk-Min, a professor at Korea National Diplomatic Academy, said, according to the AFP news agency.
South Korea on Sunday unveiled an agreement with the United States that extends the range of its ballistic missiles by more than twice its current limit to about 500 miles as a deterrent against the North.
North Korea is under heavy U.N. sanctions that have cut off its previously lucrative arms trade and further isolated the state after its failed 2009 missile test drew sharp rebukes, even from its one major ally, China.
The United States has denied it has any intention to strike North Korea. It has more than 20,000 troops stationed in the South in defense of its ally against the North.
In April, under its new leader Kim Jong-un, North Korea again launched a rocket that flew just a few minutes covering a little over 60 miles before blowing up over the sea between South Korea and China.
Reuters contributed to this report.
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