North Korea warned Thursday that a thermonuclear war can take place as the United Nations moves to impose tough sanctions against the communist country for conducting its third atomic weapons test last month.

The Rodong Sinmun, an organ of the ruling Workers' Party of Korea (WPK), said in a commentary titled "independence is more important than life" that the military has become stronger and whether there is a nuclear conflict or a war involving more powerful weapons, North Korea has the potential to retaliate.  

It didn't elaborate on the specific target of its nuclear attack.

The U.N. Security Council (UNSC) is expected to vote on fresh sanctions after Pyongyang, in defiance of international pressure, tested a nuclear weapon on Feb. 12. Before the latest test, it had detonated two atomic devices in 2006 and 2009.

"Even if Pyongyang or Washington pushed the nuclear weapons release button first, neither can legally be held accountable," the media outlet said, claiming that the country is in a heightened state of readiness and ready to strike at the heart of the enemy.

The newspaper said that with the Korean War armistice agreement having been nullified, it would not be strange if a thermonuclear war erupted.

Pyongyang announced Tuesday that it will nullify the 1953 armistice that halted the three-year-long war, while one of its diplomats said last month in Geneva that Seoul will face "final destruction" if it persists on its course to drum up support to impose sanctions on the North. Final destruction is surmised to mean a nuclear attack by Pyongyang against Seoul.

The daily also said in a separate editorial that the North can unleash an attack with the "push of a button" that would create a "sea of fire" and turn Washington and Seoul into "the final graves for aggressors." 

The "sea of fire" threat against Washington marks the second day in a row that the isolationist country used the provocative words to threaten a strike against the U.S. capital. In the past, reference to Washington as a direct target was rare.

The Rodong Sinmun then said that the Key Resolve and Foal Eagle joint military exercises being conducted by South Korea and the United States are dangerous provocations and cannot be ignored (by the North).

Reflecting the militarist stance of the country in recent weeks, the paper carried a picture of the KN-08 long-range ballistic missile set up on a mobile launch vehicle on its front page.

The missile is estimated to have a range of about 5,000 kilometers, making it an intermediate-range ballistic missile that can attack targets as far away as Hawaii.

Meanwhile, North Korean watchers in Seoul said Pyongyang seems to be upping the ante in fueling tensions to help consolidate support for the leadership among the people.

Foreign media outlets said that besides warning of its ability to use nuclear weapons, the North has started using camouflage nets to break up the outlines of civilian vehicles operating in Pyongyang.

"Such measures are more extreme than actions taken in recent years and reminiscent of measures taken about 20 years ago when the country declared it is in a quasi-state of war," a North Korean escapee living in Seoul said.

Others like Kim Yong-hyun, a professor of North Korean studies at Dongguk University, said heightening military tensions to bolster loyalty of the people is a "classic" tactic used by Pyongyang to rule the country.

Such speculations come as North Korean leader Kim Jong-un, known to be in his late 20s or early 30s, has not had time to train for his top role. Kim was not well known before he took control of the country after the sudden death of his father Kim Jong-il in December 2011. Such lack of experience has raised speculations that he may not have the kind of control over the country as exercised by his late father.

Regarding the mounting tension, Seoul said that it is keeping close tabs on the possibility that the North will launch local attacks on South Korean territory to test the resolve of the new Park Geun-hye administration, and to show its displeasure at the UNSC's actions to condemn its nuclear test and rocket launch. Park took office as the country first female chief executive on Feb. 25.

"Pyongyang made clear it plans to strike at the time and place of its choosing when it announced it is nullifying the armistice agreement," said a government official, who declined to be identified.

He speculated that the North may decide to target areas used by local civic groups who send anti-Pyongyang propaganda leaflets, or escalate tensions along the Northern Limit Line (NLL) that acts as the sea demarcation line between the two countries.

South and North Korea fought three bloody sea battles along the NLL since 1999, with inter-Korean relations coming to a halt after a South Korea warship was sunk by a North Korean torpedo in March 2010. Pyongyang also launched an artillery attack against Yeonpyeong Island in the Yellow Sea eight months after the vessel's sinking that left four people dead including two civilians.

Hong Hyun-ik, a director of securities strategy studies at the Sejong Institute, said the North could opt to launch short range missiles into the Yellow Sea or East Sea. In the past the North took such steps to show off its military prowess. (Yonhap News)