SEOUL (Reuters) - China has granted a license to a South Korean mobile game, the presidential office in Seoul said on Thursday, raising hopes of an improvement in the two countries’ relations and pushing up shares in games and entertainment firms. The presidential office said it was the first licence awarded by China to a South Korean computer game in four years -- though another Korean game, “Lucy: The Eternity She Wished For,” published by Modern Visual Arts Laboratory, had its computer version approved by China in March and its mobile version approved on Dec. 2. China has restricted sales of South Korean games, dramas and concerts as well as tours to South Korea since 2017, in a move widely seen as retaliation for Seoul’s decision to host a U.S. missile defence system. The presidential office gave few details beyond saying the licence had been granted by China on Dec. 2, and did not say what the games was called. Local media reports said Com2us had received a license from China for its popular mobile game, Summoners War. Com2us was not immediately available for comment. Its shares jumped 6.2%, and stocks of other game and entertainment firms rose sharply. China’s top diplomat, Wang Yi, visited South Korea last week after a two-day visit to Japan. “The presidential office asked China to more actively cooperate in invigorating collaboration in the culture and content areas in a recent meeting between foreign ministers of Korea and China on Nov. 26,” the South Korean presidential office said. “China also said it hopes that the two countries would continue to communicate on that matter.” The Modern Visual Arts Laboratory is an indie publisher, which is not well known in Korea, so China may not have been aware that it is a Korean game, said Wi Jong-hyun, president of Korea Academic Society of Games, an industry research group. “This is just a beginning and I’m not optimistic yet,” he said. He said the number of Korean games approved this time was small compared with other foreign games from the United States and Japan. Beijing expressed discontent over a U.S. missile defence system installed in South Korea in 2017, which Washington and Seoul say is designed to defend against North Korean missile threats but China fears could undercut its security interests.