The supply of COVID-19 vaccines for North Korea is reportedly being delayed as the communist country is failing to take administrative steps to receive the vaccines from a United Nations-backed program or COVAX.

The Voice of America (VOA) issued the report on Sunday, citing a source familiar with negotiations between North Korea and GAVI, a vaccine alliance that helps run COVAX.

The source reportedly said that the negotiations have stalled for months, with North Korea completing only two of the seven required administrative steps.

The source told VOA that North Korea has refused entry to international aid workers who could facilitate shipment of vaccines, citing COVID-19 infection concerns.

The VOA said North Korea has also expressed concerns about the safety of the AstraZeneca vaccine and has been reluctant to sign a liability waiver in case of potential side effects.

In March, Gavi said it plans to send one-point-seven million doses of the AstraZeneca vaccine to North Korea by May.