North Korea has, reportedly, reactivated one of its nuclear reactors, raising concerns that it may be bolstering its nuclear weapons program. According to a report by the International Atomic Energy Agency, the reclusive country likely reactivated its Yongbyon Reactor sometime in July this year.

The report said it had seen indications of the reactor's reactivation, including the discharge of cooling water. A report from The Wall Street Journal stated that the reactivation of the plant is "deeply troubling" as there were also signs that a nearby facility was being used to produce uranium and plutonium from spent fuel.

Plutonium and uranium can be separated from spent nuclear reactor fuel and used for nuclear weapons. Experts believe that the reactivation of the reactor may be part of North Korea's plans to ramp up its nuclear weapons program.

In recent months, North Korean leaders - including Kim Jong Un's sister, Kim Yo Jong - have threatened to enhance the nation's military capabilities in response to U.S. and South Korea's military activities. Officials have repeatedly warned that continued military exercises undermine its national security.

"The dangerous war exercises pushed ahead by the US and the South Korean side disregardful of our repeated warnings will surely make them face more serious security threat," Yo Jong said earlier this month.

North Korea had previously slammed the Biden administration for stating that the nation was a "serious threat" to global security because of its nuclear program. U.S. President Joe Biden said North Korea and Iran must not be allowed to continue with their respective weapons programs.

Shortly after he took office, Biden said that his administration's policy towards North Korea would be more diplomatic. He said the U.S. is open to talks with North Korea. However, administration officials said all efforts to arrange meetings with North Korean leaders have gone unanswered.

Former State Department official, Joel Wit, said that the reactivation of the Yongbyon terminal only serves to prove that North Korea cannot be ignored. He said the Biden administration must make the denuclearization of North Korea one of its top priorities.

Nuclear agencies estimate that North Korea could have an arsenal of more than 30 nuclear weapons and access to fissile material to produce up to 6 or 7 weapons per year.