A senior security official on Monday put aside North Korea’s latest mixed signals over its threatened nuclear test, saying a “critical point” in the conjuncture will come this week.

The communist country is believed to have completed technical preparations at its test site in the northwest town of Punggye. World attention is now focused on just when it will set off a third blast.

“Only Workers’ Party first secretary Kim Jong-un knows when North Korea will test its nuclear device,” the official was quoted as saying.

“But considering its relations with the incoming (South Korean) government, there is a considerable chance that it may carry it out before the end of the incumbent government’s term (on Feb. 24).”

Pyongyang has been seen as playing its old tactic of saber-rattling with peace offensives since it threatened a “high-level nuclear test targeting the U.S.” on Jan. 24 in response to a new U.N. condemnation of its rocket launch.

After a series of escalated threats, the North’s state media on Feb. 6 called on President-elect Park Geun-hye to boost efforts to put cross-border ties back on track, expressing its willingness to resume dialogue.

In addition, the ruling party’s official mouthpiece on Saturday accused Washington of recklessly presuming that Pyongyang will conduct a nuclear test. It argued that the U.S. will face “self-reproachable losses” from escalating tension

“The U.S. and hostile forces jumped to conclusions that the republic is planning a third nuclear test, calling for a preemptive strike if it becomes a reality,” propaganda website Uriminzokkiri said, citing state-run weekly Tongil Sinbo.

“The ugly behavior of the U.S. and hostile forces, which even know nothing about the important state measures that the republic is going to take, is like imputing blame to others.”

The government official called the North’s claim a “deceptive tactic,” saying the weekly has been used to “instigate internal conflicts in the South or create confusion.”

“North Korea has come too far to back away,” he said, adding that only a political decision remains before it comes to action.

Some Seoul officials have said that Pyongyang could test its atomic weapons on either Feb. 18, the U.S.’ Presidents Day, or Feb. 12 when President Barack Obama is scheduled to announces the State of the Union. Others suggested Park’s Feb. 25 inauguration or the birthday of Kim’s late father and longtime dictator Kim Jong-il on Feb. 16.

The forecast reflects the regime’s history of picking U.S. holidays and major political events in the two Koreas for its major provocations.

Its previous two nuclear tests were conducted on American holidays ― Oct. 9, 2006 Columbus Day and May 25, 2009 Memorial Day. It also fired rockets on U.S. Independence Day in 2006 and on the eve of late President Roh Moo-hyun’s 2003 inauguration. Other dates were related to the birthday of the North’s founding father, Kim Il-sung, and the anniversary of the establishment of the North’s ruling Workers’ Party, among others.

Given Park’s campaign pledge to build inter-Korean trust and resume humanitarian aid, the test is likely to occur before her inauguration, said Victor Cha, director of Asian studies at Georgetown University and Korean Chair at the Center for Strategic and International Studies.

“The thinking is that if it happens before the inauguration, it might give the incoming government a little bit more room politically because everybody could see it as being in response ― a sort of a farewell kiss ― to the departing Lee Myung-bak administration, which North Korea has no love for because they had a hard-line policy on North Korea,” he told the Council of Foreign Relations recently.

“On the other hand, if they conduct the test after the inauguration of the new government, then that leaves Park Geun-hye very little room to improve relations.”

By Shin Hyon-hee (heeshin@heraldcorp.com)