President Moon Jae-in has extended condolences over the death of Vietnam's President Tran Dai Quang who passed away Friday at age 61.

In a social media post Saturday, Moon called Quang a friend and partner, and said he is shocked and saddened by the news.

He said he sent a letter of condolence to the general secretary of Vietnam's Communist Party.

Moon said he first met Quang at the APEC(Asia-Pacific Economic Cooperation) summit in Da Nang last November and the two further bonded during his state visit to Vietnam this March. 

He also vowed to continue the two countries' strategic partnership ties and joint efforts to build peace and prosperity in the region.