But earlier this month she told the Security Council that if it is united, the worldwide community can cut off major sources of hard currency to North Korea, restrict oil to its military and weapons programs, increase air and maritime restrictions and hold senior officials accountable.
Defensive measures by China, undertaken in the past few months, have coincided with repeated warnings from President Trump that the United States is ready to act alone to thwart Kim's nuclear and missile programme.
The DIA has now concluded that the North Korean leader Kim Jong Un will be able to produce a "reliable, nuclear-capable ICBM" programme sometime in 2018.
She said sanctions had affected North Korea's ability to get materials for its weapons programs, but had not slowed its missile testing, as a lot of the production for this program was now indigenous.
The Office of the Director of National Intelligence, which oversees all 17 US intelligence agencies, declined to comment on any change in classified assessments.
Liu said China is still working to convince other governments to support its suspension-for-suspension proposal in which North Korea would suspend nuclear and missile tests in exchange for the US and South Korea suspending their joint military exercises.
One of the few remaining technical hurdles is the challenge of atmospheric "re-entry" - the ability to design a missile that can pass through the upper atmosphere without damage to the warhead.
The U.S., Japan, China and South Korea have been trying to figure out how to deal with North Korea's actions.
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United States and South Korean media reports cited intelligence and military officials as saying transporter vehicles carrying launching equipment had been seen on the move.
"They're setting up for something", a second United States defense official told AFP.
The US military now uses the Ground-based Midcourse Defence (GMD) system to defeat long-range missiles, such as the one that North Korea might launch to target the country. The last one, in September, had an estimated yield of 20 to 30 kilotons, more than double the explosive force of any previous test.
Independent experts said today that the missile that was launched by Kim on July 4 isn't capable of carrying a nuclear payload across the Pacific, but that may not hold for long, according to media reports.
Pyongyang made an apparent breakthrough in its weapons technology earlier this month when the authoritarian regime claimed to have successfully launched an intercontinental ballistic missile for the first time.
Economic ties between Russia and North Korea, which share a narrow land border, are similarly beleagured, with trade down for a third year to just $77 million in 2016, according to the Russian customs service.
That would be the second time Pyongyang has tested an ICBM, after its 4 July rocket launch that caused global alarm.
"The speed of North Korea's ICBM missile development is faster than the South Korean Defense Ministry expected", said lawmaker Lee Cheol-hee, of the leftist Minjoo party, who attended an intelligence committee briefing after the missile test.More news: Greece announces new 5-year bond issue after 3-year market exile
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