The Foreign Office described the situation on the Korean Peninsula as “tense following continued DPRK (Democratic People’s Republic of Korea) ballistic missile test launches”.

“You should follow the political and security situation closely and stay in touch with your host organisation or tour operator,” it said on its website.

The move by the secretive country, led by Kim Jong-un, has intensified tensions with the US and prompted US vice-president Mike Pence to state on Monday that “the era of strategic patience is over”, a comment that was widely seen as hinting at US military action, according to reports.

Intrepid Travel said that despite the uncertainty its tour to the country scheduled to depart on July 6 would “go ahead as planned”.

Beijing-based North Korea specialist Koryo Tours said it was “in regular contact with the British Embassy in Pyongyang, whose advice has not changed regarding travel to [North Korea]”.

Regent Holidays said it had not seen any “notable” impact on its North Korea programme and had no plans to cancel any trips.