SEOUL • North Korea's deputy ambassador in Britain has defected with his family to South Korea, making him the highest-ranking Pyongyang diplomat ever to flee the isolated regime for the democratic South, South Korea said yesterday.

The Unification Ministry in Seoul declined to say when or how Mr Thae Yong Ho and his family arrived, or how many relatives accompanied him.

Mr Thae defected due to discontent with the regime of Mr Kim Jong Un in North Korea and for the future of his child, ministry spokesman Jeong Joon Hee told a news conference.

"We know that Deputy Ambassador Thae is saying that his distaste for the Kim Jong Un regime and yearning for the Republic of Korea's free democratic system and the future of his child are motives for the defection," Mr Jeong said, referring to South Korea, adding that Mr Thae and his family were under government protection.

Impoverished North Korea and prosperous South Korea are technically still at war after their 1950-1953 conflict ended in an armistice, not a peace treaty.

Mr Thae's defection follows a string of recent ones by North Koreans, including 12 waitresses at a North Korean restaurant in China who defected to the South earlier this year. Those waitresses have finished a prolonged period of investigation and have entered into normal society, an official at the Unification Ministry said yesterday.

The number of defections by North Koreans to the South this year through July totalled 814, an annual increase of 15 per cent, a ministry official told Reuters.

Several diplomats from North Korea have defected to the South over the last two years, including one from Thailand, South Korea's Yonhap news agency reported yesterday, citing a source familiar with North Korean affairs.

Overall, the number of defectors, mostly from the area near North Korea's border with China, has declined since leader Kim, a third-generation dictator, took power following his father's death in late 2011.

"The bigger picture is that while there have been fewer total defections per year under Kim Jong Un, there has been a higher number of strategically significant and political defections," said Mr Sokeel Park of LiNK, a non-governmental organisation which works with North Korean defectors.

The North has become increasingly isolated after conducting its fourth nuclear test in January and numerous ballistic missile launches this year, which resulted in tightened United Nations Security Council sanctions.

Among his many responsibilities, Mr Thae was well known to the British press, acting as the embassy's main point of contact for British correspondents travelling to Pyongyang. His son, 19, has a place at Imperial College, London, to study maths and computer science, according to a school friend cited by The Guardian newspaper.

REUTERS