(CNN) First, they embraced. Then South Korean President Moon Jae-in and his North Korean counterpart, Kim Jong Un, last month planted a tree and talked alone before committing their countries to denuclearization and further talks to bring a formal end to their conflict.

At the stroke of midnight in Seoul on Saturday (11 a.m. ET Friday), the goodwill continued, with North Korea adjusting its clocks 30 minutes forward to be in the same time zone as its southern neighbor.

North Korean state news agency KCNA called the moment "the first practical step taken after the historic third north-south summit meeting to speed up the process for the north and the south to become one."

The time change was ordered by decree of the Supreme People's Assembly, the news agency reported.

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Another sign of the rapprochement will come next week, when a team from the UN's International Civil Aviation Organization will travel to North Korea to discuss a proposal to start an air route between the Pyongyang and Incheon, South Korea, airspace regions, according to Anthony Philbin, the agency's communications chief.

South Korean aviation officials are still weighing the proposal, which was requested by North Korea in February, Philbin said.

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