Israel destroyed the alleged reactor in an air raid on Syrian territory in September, but little information about the attack has been made public.

US intelligence officials briefed members of Congress on 24 April. The US claims the images show North Koreans working with Syrians at the plant. They also say it shows that the design of the Syrian reactor core was identical to that of a reactor in North Korea.

Syria has denied the allegations. Syrian ambassador to the UK, Sami al-Khiyami, told the Reuters news agency that the US had made the claims in order to put pressure on North Korea over its nuclear programme.

“This has nothing to do with North Korea and Syria,” Al-Khiyami said. “They just want to exert more pressure on North Korea. This is why they are coming up with this story. The cooperation between North Korea and Syria has nothing to do with a nuclear facility. Co-operation is mainly economic.”