​Prime Minister Chung Sye-kyun has assured the safety of the AstraZeneca COVID-19 vaccine even as he recognized concerns that the government’s decision to withhold the shots from seniors for now could be growing distrust of the British-Swedish firm's shots.

In a Friday meeting, Chung stressed that the vaccine has been authorized in some 50 countries, as well as by the World Health Organization, with none reporting serious side effects.

The prime minister then explained that the decision was based on an unclear assessment of vaccine efficacy for the elderly due to their small representation in clinical trials, though further testing is under way.

Chung said as soon as those results are out, the government will consult with experts and decide whether to vaccinate the elderly with the AstraZeneca shot.

The prime minister also warned against vaccine-related fake news and ordered relevant agencies to step up monitoring and take stern and swift measures against them.