People are strongly encouraged to stay indoors after 8pm during the first week of the strict post-Christmas lockdown, but it is not an order, health officials said on Friday night.
Under the new restrictions, all mixing of households in homes, gardens and back yards between 8pm and 6am is banned in the week from Boxing Day, except in special circumstances.
The ban on mixing is an order and will be legally enforceable, the Department of Health said. Three households are allowed to mix between December 23 and 27.
"No household mixing would be permitted in private gardens or indoors in any setting between these times," the department said.
This is "except for emergencies or the provision of health or care services or where households have chosen to form a Christmas bubble for a period of time between 23rd to 27th December with provision for travel a day either side when absolutely necessary".
"The introduction of guidance strongly advising that people should not be outside their homes between 8pm and 6am is designed to deter mixing in social settings," a department spokesperson added.
The PSNI said the new regulations, including those in effect for the week to January 2, have not yet been laid down.
"In the meantime, we can assure the public that we, as your Police Service, will continue to work with our health service colleagues and the NI Executive to slow the spread of the virus," Assistant Chief Constable Alan Todd said.
"We will do all we can to keep people safe which has been, and remains, our objective throughout the Covid pandemic."
ACC Todd added: "Until the new Regulations are enacted and come into effect on 26th December, we will continue to use our four Es approach to police the restrictions.
"We will engage with people and explain what we need them to do and encourage them to follow these restrictions."
But he warned: "The public should know that while enforcement is a last resort, we won't shy away from using it when necessary where people are in breach of the regulations."
The strong advice to remain off the streets from 8pm - which some commentators have described as close to a curfew - is not a legal order, and not directed at an individual out walking their dog in the late evening, health officials said.
ACC Todd said: "The public will continue to see a visible policing presence, with our officers on the ground across our many towns and in our cities.
"This is the most serious public health emergency in 100 years and we would appeal to everyone to continue to play their part in slowing the spread of this deadly virus and helping everyone stay safe and save lives."
The department said the guidance on staying off the streets "is particularly applicable to the first week of the lockdown".
"As with all elements of the proposed restrictions it has been introduced with the sole intention of helping to drive down levels of infection, protect hospitals from being overwhelmed and ultimately save lives," a spokesperson said.
"Businesses will be closed between these hours, by regulation, meaning reasons for going out will be greatly reduced.
"Further guidance is being developed and will be issued in coming days."