SEOUL, Jan. 1 (Xinhua) -- The Democratic People's Republic of Korea (DPRK) is expected to test-launch long-range rockets and detonate another nuclear device in 2017, a South korean expert said Sunday analyzing the New Year's address by top DPRK leader Kim Jong Un.

Cheong Seong-chang, a senior researcher at the private Sejong Institute, said in a text message that Pyongyang is forecast to test-launch a long-range rocket as early as this month before a new U.S. administration is launched on Jan. 20 in consideration of Kim's New Year's message.

The DPRK leader said his country's preparation to test-fire an intercontinental ballistic rocket had entered a final stage, citing the recent successful ejection test on the ground of a rocket engine to carry a new type of stationary satellite.

Kim's message, the South Korean expert said, indicated Pyongyang's plan to test-fire long-range rockets multiple times in 2017 to complete its intercontinental ballistic missile (ICBM) technology before a presidential election in South Korea is held later this year.

An early presidential election is expected to be held in South Korea as early as April as President Park Geun-hye was impeached in the parliament on Dec. 9.

The constitutional court has up to 180 days to deliberate whether to permanently remove Park from office, but expectations are running high for the court's final conclusion as early as February.

A presidential election must be held within 60 days after the conclusion.

The South Korean researcher predicted another atomic device detonation by the DPRK within this year as well as test-launches of Musudan intermediate-range ballistic missiles and submarine-launched ballistic missiles (SLBM).

Pyongyang conducted its fifth nuclear test in September 2016, just six months after detonating its fourth atomic device in January.

Cheong, however, forecast the DPRK would turn its hostile policy toward South Korea to a peace offensive after a new administration comes out in its southern neighbor, considering that the DPRK leader repeatedly put emphasis on the improved inter-Korean relations in his New Year's speech.

Expectations are high for the presidential power in South Korea to be transferred to the opposition bloc from the ruling camp, as support for President Park and her party sank over the influence-peddling scandal involving the president and her longtime confidante.

Major presidential hopefuls from the opposition camp have stressed the importance of dialogue with the DPRK, denouncing the Park government's hardline policy toward Pyongyang.