Image caption North Korea's London embassy is located on a residential street in Ealing, west London

A diplomat at the North Korean embassy in London has defected and fled abroad with his family, BBC News understands.

The diplomat, Thae Yong Ho, had served as deputy to the ambassador and was responsible for promoting the image of his country to British audiences.

He had reportedly lived in the UK for 10 years with his wife and family and disappeared from his home in west London several weeks ago.

Neither the Foreign Office nor the embassy has commented.

Read more: My friend the North Korean defector

"A DPRK [Democratic People's Republic of Korea] diplomat in London is going through procedures to seek asylum in a third country," a report in the South Korean newspaper JoongAng Ilbo said.

"The DPRK Embassy made belated attempts to figure out the diplomat's whereabouts, but has failed," the paper's report added, citing an anonymous source.

The paper said that in this context "a third country" means one that is neither North nor South Korea.

Analysis

Image copyright Reuters Image caption A defection would be embarrassing for North Korean leader Kim Jong-un, experts say

By the BBC's Korea correspondent Stephen Evans

North Korea has an embassy in west London. The diplomats there can be charming, particularly over curry at their favourite curry house. Their children are in nearby state schools and one is a stalwart of the local tennis club.

The other side of their lives, though, involves keeping tabs on North Korean defectors who often settle in New Malden in south-west London.

Two of the officials were probably the men who turned up at a barber shop in London to object to a picture in the window of North Korean leader Kim Jong-un, with the caption "bad hair day".

They are also thought to have escorted Kim Jong-un's brother to an Eric Clapton concert in the Albert Hall.

My friend the North Korean defector

Mr Thae's main mission in London had been to spread the message that North Korea and its leadership under Kim Jong-un had been misreported and misunderstood.

Image copyright EPA Image caption Britons would think twice about North Korea if they knew it provided free housing, Mr Thae said

In one speech, he argued that it was the British who had been brainwashed by their ruling class. "If the people in this country, or in America, knew that there is a country in the world, where there is a free education, free housing, free medical care, then they'd have second thoughts," he said, to laughter from his audience.

"That is the reason why the mass media creates all those shocking, terrifying stories about my country."

The BBC's diplomatic correspondent James Robbins says it now looks as if Mr Thae's heart may not have been in the task of defending North Korea - one of the poorest and most authoritarian countries in the world.

'Prove valuable'

"A high-level defection, if confirmed, will be deeply embarrassing for the regime," said John Nilsson-Wright, an expert on Asian affairs at the London-based Chatham House think tank.

"London has always been an important diplomatic priority for the DPRK given the amount of personnel stationed there and the considerable resources devoted by the regime to maintaining its presence there," he added.

"The intelligence benefits to the UK and its allies from such a defection are likely to prove valuable."