This photo, published on Thursday, shows Choe Ryong-hae (right), chairman of the Standing Committee of the Supreme People's Assembly, receiving a letter of credence from Cuba's new ambassador Wednesday. (KCNA)

Cuba's new ambassador to North Korea has begun his duties, according to the North's state media Thursday, as countries having friendly ties with North Korea have ramped up diplomatic activities in the secretive regime since the opening of its border.

North Korean leader Kim Jong-un was presented with the credentials of Cuban Ambassador Eduardo Luis Garcia Correa from Cuban President Miguel Diaz-Canel, according to the Korean Central News Agency.

The letter of credence was received by Choe Ryong-hae, chairman of the Standing Committee of the Supreme People's Assembly, on Wednesday upon the authorization of the North's leader, it said.

North Korea and Cuba have long maintained a close relationship since they established their diplomatic relationship in 1960.

Most diplomatic missions in Pyongyang were closed and foreign diplomats stationed in the North were asked to leave Pyongyang as North Korea shut down its border over COVID-19 in early 2020.

Cuba has become the third country known to have presented credentials for a new envoy to North Korea after China and Mongolia since last year, when Pyongyang partially opened its border.

In April 2023, China's new ambassador to North Korea, Wang Yajun, began his official duty after his arrival was delayed for years due to the North's border closure. Earlier this week, Mongolia's new top envoy to Pyongyang submitted a letter of credentials to the North.

In September last year, the Russian Embassy in Pyongyang was believed to have raised the number of its staff members. Nicaragua, a country considered to be standing against the United States, is believed to have a plan to open an embassy in North Korea soon.

"North Korea appears to be resuming its diplomacy with countries deemed to have an anti-US stance or nations with which the North has kept friendly ties based on socialism," an official at Seoul's unification ministry told reporters.

Meanwhile, North Korea has shut down nine of its diplomatic missions since the second half of last year amid economic difficulties, according to Seoul's foreign ministry. The total number of North Korean diplomatic missions had stood at 44 as of Tuesday.

The North has pulled out of Hong Kong and Libya in recent months in the latest of a series of the shutdown of its diplomatic missions, including Angola, Nepal, Bangladesh, Spain and Uganda. (Yonhap)