North Korea has been harbouring reunification ambitions since the Korean War failed to result in a peace treaty between the two sides.
Experts have warned North Korea could attempt to exploit its recent charm offensive with the South to push the US military presence out of the peninsula to strike its neighbour.
North Korea expert Bradley K. Martin warned US President Donald Trump to continue monitoring Pyongyang to avoid surprise attacks.
He said: “We should be very wary because North Korea never falters from its basic strategy which is to persuade the United States to get its troops out of the Korean Peninsula or persuade the South Koreans to push our troops out.
“And then reunite – either peacefully or forcefully – the peninsula so that North Korea will then control the southern part of the country. That is their long-term strategy.”
North Korea has been encouraging fears of World War 3 with its refusal to shut down its nuclear and missile development programmes.
Earlier this month leader Kim Jong-un unexpectedly accepted South Korean offers to organise diplomatic meetings with South Korea, sparking concerns Pyongyang would attempt to convince the international community to ease economic sanctions on the rogue nation in a distracting charm offensive.
But Mr Bradley told CBC North Korea would never “waver” on its long-established strategy of aggression.
He said: “They are trying to break down the alliance and the determination of South Korea and use their own intensity.
“The North never wavers, never changes its strategy. They have been doing the same thing all these years.”
Despite a successful first meeting between officials in the demilitarised zone (DMZ), North Korea dramatically pulled out of a second meeting scheduled for this weekend.
South Korean news agency Yonhap reported Kim Jong-un failed to provide an official reason for the sudden cancellation.
The new set of talks would have centred around North Korea’s plans to send a 550-delegation to South Korea for next month’s Winter Olympics.
Earlier this week North and South Korea agreed to march under a ‘unity flag’ at the Games, to be held in Pyeongchang County.