South Korean President Moon Jae In addressed rumors about the country's plans to scale back its joint military drills with U.S. if North Korea agrees to freeze its nuclear activities. Moon said Wednesday that reducing the joint military exercises was not an option for now.

"First of all, the official position we have now is that North Korea's nuclear freeze and reduction of joint military exercises between South Korea and the United States cannot be linked," Moon said, according to Yonhap News. "That has been the official position of South Korea and the United States, and that position has not changed," he added. Moon's comments came on board Air Force One, on his way to Washington, D.C., for a summit with his U.S. counterpart, Donald Trump.

Read: Kim Jong Un's Regime Won't Negotiate Over Nuclear Program, Report Says

Moon also said reducing the joint military drills — seen as a threat by North Korea — could be considered only after irreversible and verifiable steps by Pyongyang to denuclearize. North Korean leader Kim Jong Un's regime has conducted five missile tests since Moon took office in May. 

Last week, Moon's special security adviser, Moon Chung In, claimed Seoul and Washington may consider reducing their joint military drills should the North freeze its nuclear activities. However, he said he was speaking within his personal capacity.

Moon Chung In's remarks sparked concerns that Seoul's new liberal government may be considering making such an offer to Pyongyang despite the North's continued nuclear and missile provocations.

"I do believe the notion that we must not reward bad behavior is a principle we must uphold," the new South Korean president told reporters. "The most ideal solution would be to completely denuclearize North Korea in an one-shot deal. But more realistically, I believe such a deal will not be easy."

"I believe (the North) must at least promise to a nuclear freeze for us to start taking serious measures (discussions) for its denuclearization. In that sense, its nuclear freeze will be the entrance and nuclear dismantlement the exit," he added.

North Korea has been conducting missile launches, amid increasing tensions in the Korean Peninsula despite receiving tough sanctions and warnings from the United Nations.

The South Korean president expressed hope his summit with Trump would mark the start of discussions on ways to end North Korea's growing nuclear weapons program. The two leaders are set to hold their first bilateral talks Friday.

Read: North Korea Can Produce Hydrogen Bomb But Is Not Likely To, Stanford Professor Says

The summit also comes amid North Korea's threat to execute South Korea's former President Park Geun Hye over an alleged plot to assassinate Kim Jong Un.

"We declare at home and abroad that we will impose the death penalty on traitor Park Geun Hye," the statement said, according to a report by the Guardian. The statement alleged that Park had "pushed forward" with the attempted plot by Seoul's intelligence services. Pyongyang also said former director of South Korea's National Intelligence Service (NIS), Lee Byung-Ho, would also be executed along with sympathetic groups.

They "can never make any appeal even though they meet miserable dog's death anytime, at any place and by whatever methods from this moment," the statement read, adding that the accused ex-president and former director should be handed over as "organizers of the hideous international terrorist crimes."