Stormont ministers met for several hours into the evening on Thursday, eventually agreeing to impose a shutdown on 26 December, the PA news agency reported.
Measures to be announced are expected to include the closing of all non-essential retail as well as close-contact services, while the hospitality sector will be confined to takeaway services only.
There are expected to be no changes made to the Christmas bubbling arrangements.
Ahead of Thursday’s executive meeting, economy minister Diane Dodds said Northern Ireland was in an “extremely challenging position” in terms of the virus’s transmission.
UK news in pictures
Show all 50
“I have said over and over again how difficult this cycle of lockdown is for the economy, we have published data on the cost of the cycle of lockdown to the economy, but we’ll wait and see what the discussion at the executive brings forward,” she said.
Case numbers continue to rise in Northern Ireland despite the latest two-week circuit-breaker, with hospitals across the country running over capacity.
Earlier on Thursday, the Northern Ireland Ambulance Service announced that paramedics from the Irish Republic would be drafted in to help – which the service’s chief executive Michael Bloomfield said was “relatively unusual” and reflects the pressure they are under.
Two days prior, ambulances were witnessed queueing at emergency departments across Northern Ireland, as patients were treated in car parks due to a lack of capacity inside hospitals.
The expected lockdown announcement follows Mark Drakeford’s announcement that all non-essential shops will be forced to close in Wales after Christmas Eve, with tighter lockdown restrictions for household mixing and staying-at-home guidance to be introduced from 28 December.
And in Scotland, deputy first minister John Swinney also refused to rule out a post-Christmas lockdown on Thursday.
He said the Scottish Government would review the situation next Tuesday as part of an unplanned “decision-making moment” – a move he said reflected the “deteriorating situation”.
Additional reporting by PA