A potential third wave of Covid-19 in Northern Ireland could be the worst yet, Stormont’s health minister has warned.

Robin Swann said the rollout of the vaccine was a welcome development but it could lead to complacency and a slipping of compliance with coronavirus restrictions.

“This pandemic is far from finished,” he said.

“Indeed, I’m still very concerned that the next surge in infections could in fact be the most aggressive yet.

“Our health service remains under immense pressure, staff are already exhausted and are increasingly fearful over what they will have to face in the weeks ahead.”

His warning came as chief scientific adviser Professor Ian Young said people had not restricted their movements during the current two-week circuit-breaker as much as officials had hoped.

“Therefore we’re not going to see the full benefit that we hoped for from these two weeks of restrictions,” he added.

Professor Young said a one-week relaxation of restrictions ahead of the start of the current circuit-breaker had led to a 25% increase in case numbers.

He said the R reproduction rate increased to 1.2 after that week.

Prof Young said R was currently around 1.

He said the region was facing a “potentially difficult and risky period” with the relaxation of restrictions over the festive period.

The deaths of a further 12 people with Covid-19 in Northern Ireland were announced on Wednesday.

An additional 482 people tested positive for the virus.

Addressing a Stormont media briefing, Mr Swann said a third wave was “not inevitable”.

But he added: “That third surge is something we must prepare for.”

The minister said people had the power to prevent another surge by restricting their interactions over the coming weeks.

He said it would be a “shame and disgrace” if the “careless actions” of some people led to another wave of cases when the benefits of the vaccine were so close.

Mr Swann said the development of an effective vaccination meant the finishing line in the battle against Covid-19 was in sight.

“Now is not the time to stumble,” he added.

Asked if he was comfortable that restrictions on certain sectors would lift on Friday, Mr Swann stressed that “intensive work” had been undertaken to reduce the risk associated with the reopening of sections of the economy.

Chief medical officer Dr Michael McBride also stressed the need for ongoing compliance with the Covid-19 regulations.

“For 10 long months we have kept our distance and missed our friends and family,” he said.

“Please remember why you were doing this and please remember the end has not yet arrived.

“We have come too far, sacrificed too much and please, if you think it’s over, it’s not.

“Do not let your actions today and tomorrow and in the coming weeks result in an empty chair at your table in the new year.

“So let’s all continue to work hard until the vaccine does the work for us.”