The timing of North Korea’s possible nuclear test still remains unclear, with the tension expected to enter the most critical phase this week, a senior official in Seoul said Monday. The official was quoted by South Korean News Agency (Yonhap) as saying that South Korea is keeping close tabs on the North’s nuclear test site in its northeastern region, as Pyongyang is likely to carry out the test before President-elect Park Geun-hye is sworn in on Feb. 25. After Pyongyang warned last month of a third atomic test without specifying a date, many have bet on late leader Kim Jong-il’s Feb. 16 birthday or other potential dates in the coming week, including U.S. President Barack Obama’s State of the Union Address on Feb. 12 and Presidents’ Day on Feb. 18. “Only North Korean leader Kim Jong-un knows the exact date of nuclear test,” said the official, asking to remain anonymous. Adding to the confusion over the prickly neighbor’s intentions, a Japan-based pro-North weekly magazine, Tongil Sinbo, on Friday accused the United States and its allies of misinterpreting North Korea’s pledge to implement “important measures” as a third nuclear test. Officials in Seoul, however, played down the latest remark, saying the communist country will go ahead with the test and its timing will be politically motivated. “There is a possibility of the North conducting a test before the current administration’s term ends, considering its relationship with the incoming government,” the senior official said. “The North has come too far to step back at this point. It has already finished preparations for a test and is only awaiting a political decision.” President-elect Park, who campaigned on mending ties with Pyongyang, has repeatedly urged the North to drop the test plan and warned of further isolation in case of provocations. Although only North Korean leader Kim Jong-un knows for sure when the country plans to pull the trigger, the official said a “critical moment” could come this week, hinting at an imminent test. The official played down Tongil Sinbo’s editorial as a “manipulative tactic” aimed at creating confusion in the South, saying the outlet doesn’t represent the North’s official position. South Korea’s foreign affairs and national security team at the presidential office remain on high alert, keeping its hotlines with other concerned ministries open and sharing information with newly appointed security advisers of the incoming government, according to officials. Last month, the U.N. Security Council toughened sanctions on the isolated country for carrying out a long-range rocket launch in December. The North has claimed the launch was intended to put a satellite into orbit, but South Korea and the U.S. denounced it as a disguised test of missile technology.