NEW YORK (Yonhap) -- U.N. Secretary-General Ban Ki-moon said Tuesday he expects global leaders will discuss the North Korean nuclear issue when they meet in Seoul later this month for a summit on nuclear safety and security.

South Korea is scheduled to host the second Nuclear Security Summit from March 26-27 in which the heads of state from more than 50 nations and leaders of international organizations including Ban will take part.

The biennial summit does not have the North's nuclear problem as a formal agenda since it is not designed to deal with nonproliferation issue of a specific nation, Ban said in an interview with Yonhap News Agency at his office in New York.

"I think discussions (on the matter) are possible on the sidelines such as through bilateral consultations, since leaders of the world's major countries participate (in the summit)," he said.

Ban, formerly a South Korean foreign minister, said participants will be able to express support for the six-way nuclear talks and the denuclearization of the Korean Peninsula, which will eventually contribute to global efforts to bolster nuclear security.

He was skeptical of the possibility that Pyongyang will join the Seoul session, citing the communist nation's internal situation and its responses to the South's invitation.

Ban said, meanwhile, the U.N. will put forward several action plans to beef up the multilateral nuclear security and safety.

He said toughening financial sanctions are necessary to prevent the spread of weapons of mass destruction and nuclear terrorism.

Above all, Ban stressed, it is important to tackle the production and transfer of highly enriched uranium (HEU), plutonium and other fissile materials.

On South Korea, he said he was proud that his motherland will host the Nuclear Security Summit, the highest-level forum on international security, after the G-20 summit was held in Seoul.

"The summit this time is meaningful in that the stature of the Republic of Korea (South Korea) has been recognized not only in economy but also in the international security field," Ban said. "I think South Korea's national brand will be upgraded by one notch through the success of the summit this time."