After historic signs of warmth across the demilitarised zone and an apparent willingness to shutter key nuclear test facilities ahead of the summit between Donald Trump and Kim Jong-un, Pyongyang has suddenly signalled a tougher approach that rattled nerves around the region.
It came as a shock when the North suspended high-level inter-Korean talks planned for Wednesday in protest against joint US-South Korean air manoeuvres, and even threatened to reconsider the June 12th summit with the US planned for Singapore.
Although the announcement sparked fears that Pyongyang could make a U-turn on recent moves towards peace, most analysts see it as a strategic means of extracting more concessions from Washington and Seoul.
North Korea views US-South Korean drills as nothing less than a precursor to invasion, and has long claimed that the reason for its nuclear weapons programme has been to protect itself against US aggression.
The US and South Korea are currently staging the Max Thunder air force exercise, which runs until May 25th, and involves the deployment of 100 aircraft, including key US assets such as eight F-22 radar-evading fighter jets.
John Delury, an associate professor at the Yonsei University Graduate School of International Studies in Seoul, said throwing a wrench in the diplomatic process over what seemed like a "little thing" could be viewed as typical North Korean behaviour.
“Then decisions have to be made: Do we address their concern, risking a slippery slope?” he said.
“Or do we ignore the warning and steam ahead, risking success in the larger sense? Or is there a middle way – a tweak that doesn’t cost us too much but shows we are listening, meeting halfway?”
Goodwill gestures
The North Koreans have made a remarkable series of small but concrete goodwill gestures, such as suspending their intercontinental ballistic missile programme and ending the nuclear tests, as well as releasing three American detainees and meeting South Korean president Moon Jae-in on the southern side of the demilitarised zone (DMZ).
“Perhaps Kim Jong-un could feel the need for Moon Jae-in and Donald Trump to do him a solid [favour],” said Delury.
During the long-stalled six-party talks, chaired by China and involving both Koreas, Russia, the US and Japan, the North would often display astonishing intransigence. Negotiators spoke of walls of silence and frustration with a hostile approach that made compromise impossible.
So it did come as some surprise when the North Koreans suddenly appeared so accommodating and willing to come halfway on many of the demands set out to secure peace on the Korean peninsula.
Regime security
Park Won-gon, a security expert at Handong Global University, said the move seemed to be a negotiating tactic aimed at helping the North secure the high ground in the denuclearisation talks, particularly on the thorny issue of a guarantees for regime security.
“After all, the North is thinking of two major issues, namely the military drills and Washington’s deployment of strategic assets to the peninsula. It wants to address the issues rather than spoiling the momentum for talks,” Park told South Korea’s Yonhap news agency.
Koh Yu-hwan, a professor of North Korean studies at Dongguk University, said the North believes that Seoul and Washington are not playing fair.
“Pyongyang appears to believe that even though it has taken its own unilateral measures to put a moratorium on nuclear tests and dismantle the test site – all intended to build trust – there hasn’t been any change in the stances of Seoul and Washington,” Koh said.
Moon Jae-in’s team are trying to calm nerves.
“We believe the current situation is part of a difficult process to draw the same picture and that it is a pain we must endure to get good results,” said Yoon Young-chan, the senior press secretary to the president.