One, called Gomi, has now given birth to three female and three male offspring.
President Moon shared photos of the dogs on the official Blue House Twitter feed on Sunday but did not say what the new arrivals would be called.
“As the pregnancy period of dogs is about two months, Gomi must have come to us pregnant,” he said. “I hope inter-Korean affairs will be like this.”
Days after the puppies were born, South Korea flew military planes filled with tangerines to the North’s capital Pyongyang, the BBC reports. The North had previously sent pine mushrooms over the border.
The exchange of gifts comes following a series of three historic meetings between Mr Moon and Mr Kim this year.
In September, Mr Moon became the first South Korean leader to give a speech to the North Korean public. He received a standing ovation from 150,000 people after speaking at the country’s Arirang Games, a major propaganda set piece in there. He has also acted as a mediator between Mr Kim and US President Donald Trump, who met each other in Singapore in June.
More recently, Mr Moon said he was confident the Korean War could soon be concluded.
The two countries are still technically in a state of hostilities having ended the 1950-53 conflict with a ceasefire rather than a peace treaty.
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