The UN Security Council echoed international condemnation Sunday of a submarine-launched ballistic missile (SLBM) test by North Korea, while US President Barack Obama dismissed Pyongyang's offer of a nuclear moratorium.
Saturday's test, personally monitored by supreme leader Kim Jong-Un, was the latest in a series of provocative moves by Pyongyang that have further fuelled tensions on the divided Korean peninsula following the North's fourth nuclear test back in January.
There are growing concerns that Pyongyang is building up to a fifth nuclear test ahead of a key political gathering early next month.
The Security Council said the SLBM launch marked a "serious" violation of UN resolutions aimed at curbing the North's nuclear drive, and urged Pyongyang to refrain from any further provocations.
A proven SLBM capability would take North Korea's nuclear strike threat to a new level, allowing deployment far beyond the Korean peninsula and the potential to retaliate in the event of a nuclear attack.
Kim Jong-Un hailed the test as an "eye-opening success" that underlined the country's ability to strike South Korean or US targets "anytime".
South Korea's defense ministry said the missile, fired from a submarine in the Sea of Japan (East Sea), flew around 19 miles (30 kilometers) and demonstrated clear technological progress from previous tests.
Deployment could begin in three to four years if Pyongyang dedicates enough resources to the project, ministry spokesman Moon Sang-Gyun told reporters.
Hours after the launch, North Korean Foreign Minister Ri Su-Yong, speaking in New York, said Pyongyang would be willing to halt further nuclear tests if Washington announced an end to its joint military exercises with Seoul.
The annual drills always raise tensions on the Korean peninsula, with the North condemning them as provocative rehearsals for invasion
The United States had flatly rejected the same moratorium offer made by the North in January last year, and Obama, currently on a visit to Germany, was equally dismissive this time around.
"We don't take seriously a promise to simply halt until the next time they decide to do a test," the president said during a joint press briefing with German Chancellor Angela Merkel.
"They're going to have to do better than that," he added.
South Korea also waved off what it described as a "ridiculous attempt" to link sanctions-violating nuclear tests with regular military exercises.
Clear and present threat
At the same time, Obama warned of the very real dangers posed by North Korea's continued weapons testing, including the recent SLBM launch.
"Although, more often than not, they fail in many of these tests, they gain knowledge each time," he said.
"We take it very seriously, so do our allies and so does the entire world," he added.
North Korea's state television showed pictures of the missile, emblazoned with the name "North Star," trailing a large plume of smoke as it soared out of the water.
It also showed what it claimed were underwater images of the missile being ejected from the submarine, using key "cold launch" technology.
Experts have suggested that the North's previous SLBM tests were conducted from a submerged platform.
North Korea is currently gearing up for a rare and much-hyped ruling party congress -- the first in 36 years -- at which Kim is expected to take credit for pushing the country's nuclear and missile weapons program to new heights.
In recent months, the North has claimed a series of significant technical breakthroughs, including success in miniaturising a nuclear warhead to fit on a missile and testing an engine designed for an inter-continental ballistic missile that could reach the US mainland.