The US special envoy for North Korea has raised concerns of possible provocations by Pyongyang as the country observes the 110th anniversary of the birth of its founder on April 15.

The birth anniversary of Kim Il Sung, the grandfather of current leader Kim Jong Un, is regarded as one of North Korea's biggest national holidays. The country's leadership has said the 110th anniversary will be celebrated on a grand scale.

US Special Representative for North Korea Sung Kim responded to questions from reporters on Wednesday in a teleconference.

He said in terms of the upcoming anniversary and the provocative action North Korea may take, "it could be another missile launch, it could be a nuclear test."

He also expressed eagerness to strengthen the deterrence capability of the US, South Korea and Japan. He said he knows that "our colleagues in the military are also considering what we can be doing together bilaterally as well as trilaterally."