Passenger trains between China and North Korea will resume service on Thursday, reviving a transport link that was shuttered for six years due to the pandemic, China's rail operator said.

Trains between Beijing and Pyongyang will operate four times a week, while the service between the Chinese border city of Dandong and the North Korean capital will run daily, China Railway said in a notice late Tuesday.

The train services are "a moving link that strengthens the friendship between China and North Korea," China Railway said.

While China has completely reopened from the pandemic, North Korea has been doing so slowly, allowing a limited number of tourists to enter from 2024.

International travellers are allowed on certain train carriages on the Beijing-Pyongyang service, according to China Railway.

But a travel agent told the BBC that the tickets are not yet available for businessmen or tourists. The agent said only people with valid visas can buy the tickets.

According to the AFP news agency, current visa holders include Chinese citizens who work or study in North Korea and North Koreans who work, study, or need to visit family abroad.

Tickets for the first train departing on Thursday have sold out, Reuters reported, citing an official ticketing office in Beijing. It also reported that those who purchased tickets were entrepreneurs, government officials and reporters.

On Tuesday, Chinese foreign ministry spokesperson Guo Jiakun said that maintaining regular passenger train services between the two countries "is of great significance" for facilitating exchanges between people.

Earlier this week, North Korean leader Kim Jong Un said in a letter to Chinese President Xi Jinping that he believed cooperation between their countries would grow closer "on their common path to advance the socialist cause".

The letter was in response to a message sent by Xi last month congratulating Kim for being named again as the leader of his party.

Chinese tourists made up a major share of foreign tourists to North Korea until the country sealed itself off at the start of the pandemic in early 2020.

North Korea slowly opened back to tourists in 2024 has launched new projects such as a seaside resort in an attempt to boost tourism, though such initiatives have also faced suspensions.