Injections of the Oxford/AstraZeneca coronavirus vaccine start in Northern Ireland GP practices this afternoon.
A batch of 50,000 doses has been allocated and those aged over 80 will be prioritised initially.
The country has moved to accelerate delivery of the jab as the pace of the pandemic has picked up and a new and more infectious variant of Covid-19 has been detected in Northern Ireland.
Chief medical officers across the UK have decided to delay delivery of the second shot of vaccines.
The intention is that the maximum number of people receive their first jab, with its partial protection, as quickly as possible to help step the tide of cases which threatens to overwhelm the health service.
Northern Ireland is in the second week of a six-week lockdown in which non-essential retail is closed.
The country has recorded a further 1,662 cases of Covid-19.
A total of 11,810 people have tested positive in the last seven days, the Department of Health said on Sunday.
Another six people have died.
Stay with us throughout the day for all the latest on this developing story.
