North Korea crossing a red line if it launches ICBM again: South Korea's Prez

North Korea would be "crossing a red line" if it put a nuclear warhead on an intercontinental ballistic missile, South Korea's president said on Thursday, but the United States had promised to seek Seoul's approval before taking any military action.

North Korea's rapid progress in developing nuclear weapons and missiles capable of reaching the US mainland has fueled a surge in tensions in recent days. Pyongyang has threatened to fire missiles towards the Pacific island of Guam and US President Donald Trump has warned it would face "fire and fury" if it threatened the United States.

"I would consider that North Korea is crossing a red line if it launches an intercontinental ballistic missile again and weaponizes it by putting a nuclear warhead on top of the missile," South Korean President Moon Jae-in said at a news conference marking his first 100 days in office.

Moon has repeatedly urged North Korea not to "cross the red line" but had not previously elaborated what that would constitute.

Trump had promised to seek negotiations and approval from South Korea before taking any options regarding North Korea, Moon also said.

The United States and South Korea remain technically still at war with North Korea after the 1950-53 Korean conflict ended with a truce, not a peace treaty.

Washington has warned it is ready to use force if needed to stop North Korea's ballistic missile and nuclear programs but that it prefers global diplomatic action.

"No Military Solution"
US Vice President Mike Pence told reporters in Chile on Wednesday that "all options" remained on the table with regards to North Korea, and he called on Latin American nations to break ties with Pyongyang.

However, White House chief strategist Steve Bannon said there was "no military solution" to North Korea's nuclear threats because of Pyongyang's massed artillery targeting the South Korean capital.

"Until somebody solves the part of the equation that shows me that 10 million people in Seoul don't die in the first 30 minutes from conventional weapons, I don't know what you're talking about, there's no military solution here, they got us," Bannon told The American Prospect.

China, North Korea's main ally and trading partner, has repeatedly urged Pyongyang to halt its weapons program and at the same time urged South Korea and the United States to stop military drills in order to lower tensions.

Bannon said he was pushing the US administration to take a harder line on China trade and not put complaints against its trade practices in the backseat in the hope that Beijing would help restrain leader Kim Jong Un.

"To me, the economic war with China is everything. And we have to be maniacally focused on that," The American Prospect quoted Bannon as saying.

North Korean media reported on Tuesday that Kim had delayed the decision on firing four missiles towards Guam, a US territory home to a vital air base and Navy facility, while he waited to see what the United States did next.

"Kim Jong Un of North Korea made a very wise and well reasoned decision," Trump wrote on Twitter on Wednesday. "The alternative would have been both catastrophic and unacceptable!"