A South Korean state-run think tank said Wednesday that North Korea may heighten tensions with new nuclear and missile tests early next year as the Donald Trump administration takes over.

"The North is expected to intensify its push to deploy nuclear weapons for combat use through its sixth nuclear test and ballistic missile launches next year," the Institute for National Security Strategy (INSS), a think tank run by the National Intelligence Service, said in a report.

"The likelihood is high that provocations including a nuclear test in the first half coupled with missile launches could prompt more confrontation and eventually send the inter-Korean relations into no visibility," it added.

The INSS said that the North could conduct a nuclear test, in particular, in January and February when it is to celebrate major anniversaries such as birthdays of Kim Jong-un and his late father Kim Jong-il.

The think tank worried that the North's additional provocation would result in more diplomatic pressure from the incoming Donald Trump administration, heighten tensions and prompt yet another nuclear crisis in the region.

The INSS said that the Kim Jong-un regime may launch a peace offensive by pursuing talks with the US and South Korea in the second half but if the attempt does not pan out, it could resort again to provocative measures.

The North conducted its fifth nuclear test in September, drawing strong condemnation from the international community. In November, the UN Security Council adopted a new set of sanctions aimed at making it hard for Pyongyang to obtain hard currency that can be exploited to pursue its nuclear ambitions.

The US and South Korea have said that there will be no talks with the North until it shows meaningful action toward denuclearization. (Yonhap)