GYEONGJU, South Korea/BEIJING, Nov 1 (Reuters) - Chinese

President Xi Jinping gifted South Korea's President Lee Jae

Myung a pair of Xiaomi ( XIACF ) smartphones and jokingly urged him to

"check if there's a backdoor," during a state visit on Saturday

that capped the Asia-Pacific Economic Cooperation (APEC) forum.

Lee hosted Xi at a state summit and dinner after the APEC

leaders' meeting in the South Korean city of Gyeongju, marking

Xi's first visit to the U.S. ally in 11 years.

The choice of the gift - China-made Xiaomi ( XIACF ) devices

brought to the home country of smartphone giant Samsung

Electronics ( SSNLF ) - underscored Xi's technological

ambitions, recently reinforced in China's economic development

plan for the next five years.

After Lee presented Xi with "the finest" wooden board for

ancient strategy game Go, the pair walked over to the

smartphones wrapped in black boxes and an official noted the

displays on the devices were made in South Korea.

Lee lifted one of the boxes and looked at it. He then asked

Xi: "How is the communication security?", upon which Xi and

other gathered officials erupted in laughter. Xi then pointed at

the phones and responded: "You can check if there's a backdoor."

A backdoor risk refers to a hidden method of bypassing

normal authentication or security controls.

Both leaders laughed and Lee clapped his hands as they

proceeded with the presentation of gifts, which also included a

traditional Korean mother-of-pearl inlay lacquered tray.

Xi's comment harkened back to concerns expressed by China

over a U.S. proposal for advanced chips sold abroad to be

equipped with tracking and positioning functions that prompted

U.S. chipmaker Nvidia ( NVDA ) to say its chips had no

"backdoors".

China's foreign ministry and Xiaomi ( XIACF ) did not immediately

respond to Reuters' requests for comment on the exchange. Lee's

office said it had no separate comment on Xi's gifts.

At the summit, Lee sought Xi's help in efforts to resume

talks with nuclear-armed neighbour North Korea, while Xi told

Lee he was willing to widen cooperation and jointly tackle the

challenges they face.

In other recent off-the-cuff remarks by Xi, a hot mic caught

the Chinese leader and Russian President Vladimir Putin

discussing organ transplants and the possibility that humans

could live to 150 years at a military parade in Beijing in

September.