Health minister Robin Swann said it was "a clear sign of progress" there was no Covid-19 deaths recorded on Tuesday, but warned against complacency.
The Department of Health figures referred to no new deaths in the last 24-hour reporting period, nor newly notified deaths, leaving the total in the region at 514.
However, the daily update did record a further 28 confirmed positive cases ofthe virus, bringing the total number in Northern Ireland to 4,637.
The number of deaths is just a fraction of the potential 14,000 warned of by Mr Swann in March before strict social distancing rules were introduced to stem the spread of the virus.
It comes just 24 hours after the Republic of Ireland reported no new Covid-19 deaths on Monday.
Mr Swann told Stormont's daily press conference: "We all have been waiting for a day like this".
"I do believe it is a clear sign of the progress that has been made in thebattle against coronavirus, however I have to emphasise a serious note ofcaution," he said.
"There are no grounds whatsoever for complacency - that would be insult to all those who have sadly lost their lives and to all those who are mourning them.
"Covid-19 is still infecting people in our community, sadly there will be morelives lost in the days and weeks ahead.
"However there is a clear downward trend in the rolling average number ofcases and deaths that we are reporting."
He added: "If people get it into their heads that this emergency is over, theconsequences will be catastrophic."
"A second wave of the virus is also expected in the months ahead so we must keep our defences up."
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