The Queen’s message was also carried on page two of the state newspaper, Rodong Sinmun, on Sunday, alongside other foreign leaders who sent greetings, among them, Xi Jinping, the Chinese president.
“We need to know who has changed their policy: the UK, sending for the first time? Or North Korea, publishing for the first time,” Mr Foster-Carter added. “If the former, further questions arise. Why now? And on whose initiative?”
North Korea is also believed to have sent past messages to the Queen to mark her official birthday.
The Kim dynasty has long placed great emphasis on gifts and messages from international dignitaries as a sign of its international legitimacy, despite the regime’s status as a pariah nuclear-armed state.
However, it is rare for the reclusive and paranoid Kim to meet with other foreign leaders or to leave the country over which he has a tight, authoritarian grip. His hermit state has become further isolated after sealing its borders to keep out the coronavirus.
Kim’s pre-Covid trips
Before the pandemic, he made several trips to China, North Korea’s largest trading partner, and attended a summit with Vladimir Putin, Russia’s president.
In 2018, Donald Trump made history by becoming the first sitting US president to meet with a North Korean leader, when they held talks in Singapore aimed at dismantling Pyongyang’s nuclear weapons facilities.
Negotiations fell apart at a 2019 summit in Vietnam, when they failed to reach a deal on the easing of punitive international sanctions, and the diplomatic détente has not resumed since.
The UK has maintained an embassy in Pyongyang since 2000, although it is currently closed due to the country’s severe pandemic restrictions.
“Her Majesty’s statement underscores the fact that the UK has diplomatic relations with the DPRK. It would be unwise to speculate on the precise reason for this particular message,” said Edward Howell, a North Korea analyst at the University of Oxford.
“The UK’s policy towards the DPRK remains one of ‘critical engagement’: calling on the North to end its nuclear development and human rights violations, and engage in dialogue with the US.”
A Foreign Office spokesman said: “As in previous years, The Queen has sent a message to the people of the DPRK on the occasion of their national day.”