The Biden administration has extended for one year a Trump-era ban on the use of US passports for travel to North Korea

The ban was first imposed by former secretary of state Rex Tillerson in 2017 after the death of American student Otto Warmbier, who was injured while in North Korean custody. It has been extended annually ever since.

The State Department announced the extension of the ban until August 31 2022, in a Federal Register notice to be published on Thursday.

Humanitarian groups have expressed concern about the impact the initial ban and its extensions have had on providing relief to isolated North Korea.

The ban makes it illegal to use a US passport for travel to, from or through North Korea, also known as the Democratic People’s Republic of Korea, or the DPRK, unless the document has been specially validated.

Such validations are granted by the State Department only in the case of compelling national interest.

“The Department of State has determined there continues to be serious risk to US citizens and nationals of arrest and long-term detention constituting imminent danger to their physical safety,” the department said in the notice.

“Accordingly, all US passports shall remain invalid for travel to, in, or through the DPRK unless specially validated for such travel under the authority of the Secretary of State.”

Mr Warmbier was part of a group tour of North Korea and was leaving the country in January 2016 when he was arrested for allegedly stealing a propaganda poster.

He was later convicted of subversion and sentenced to 15 years in prison.

In June 2017, North Korean authorities reported to US officials that Mr Warmbier had suffered extensive injuries while in custody, and former US president Donald Trump’s administration sent a delegation to repatriate him.

Mr Warmbier, who was comatose, died in a Cincinnati hospital six days after his return to the US. Shortly after, Mr Tillerson imposed the ban on the use of US passports for travel to North Korea.