A former US nuclear negotiator said Thursday that Washington needs to push for normalizing relations with North Korea and make efforts to sign a peace treaty that ends the 1950-53 Korean War, as Pyongyang's ultimate goal is to secure its regime and leadership.

Joseph DeTrani also said during a virtual seminar that recognizing North Korea as a nuclear weapons state is not a "viable option" because such recognition would facilitate an arms race and cause instability in the region.

"We know it's security for the regime, security for the leadership. That's the ultimate objective," said the former US special envoy for six-party nuclear talks during the conference hosted by the state-run Institute for National Security Strategy (INSS).

"So when, once, we can build some trust and move forward with security assurances and then move toward the path toward normalization of relations and the peace treaty that finally ends the Korean War -- these are positive things," he said.

DeTrani said that the North has conducted nuclear weapons and intercontinental ballistic missiles (ICBMs) tests for years and showcased a new and large ICBM during a massive military parade in October, but the regime sees those weapons as a deterrent as it worries about regime change.

"Having negotiated with North Korea for a number of years and having had contact with North Korea for a number of years, they see it very clearly as a deterrent and they are concerned about regime change," he said.

He called for continued efforts to resolve the North's nuclear issue through diplomatic efforts but stood firm against the idea of recognizing North Korea as a nuclear state, saying that it could spark an arms race and instability in the region.

"North Korea with nuclear weapons will facilitate and will encourage others, whether it's Republic of Korea, whether it's Japan, whether it's Taiwan," he said. "A number of other countries would seek their nuclear weapons capability regardless of US extended nuclear deterrence commitment to these countries, allies and partners.""I think North Korea retaining nuclear weapons, which is their goal, and being accepted as a nuclear weapon state like we, the US accepted, recognized Pakistan, should not be a viable option.

It should not be an option per se because of the likelihood of proliferation in the region," he added.

DeTrani served as North Korea mission manager at the Office of the Director of National Intelligence from 2006-2010. He also worked as the State Department's special envoy for the six-party talks from 2003 to 2006. (Yonhap)