The letter has been published in the North of Ireland’s daily newspapers today, Saturday, May 23.
In it, Arlene Foster and Michelle O’Neill say because of the public’s actions, the infection rate here has reduced and lives have been saved.
They also appealed to the public to keep following the rules and advice.
First Minister Arlene Foster said that Northern Ireland had reached a stage where some of the “very challenging restrictions” could be relaxed.
“That is thanks to the actions of people in Northern Ireland” she said.
“It is right that we acknowledge the part that individuals have played in saving lives.
“But it’s also important we remind people that we’re not yet out of the woods.
“We are still depending on people to follow the restrictions that do remain in place; to observe social distancing; and maintain good hygiene.
“Those measures are still critical in our efforts to save lives.”
Deputy First Minister Michelle O’Neill said recovery from coronavirus would only be possible “if we work together to beat it”.
“As our partners in this process, we have committed to keeping the public updated every step of the way as we gradually move out of lockdown,” she said.
“So we felt it was important that we write to update the public on the current situation and thank them for the part they have played in getting us to this point.
“The role of every member of society is still crucial on the journey towards recovery.
“The better we all follow the advice and regulations that are in place, the sooner we can come out the other side of this together.”The first measures to ease the lockdown began last week, with as many as six people who do not share a household allowed to meet outside – as long as they follow social-distancing guidelines and stay two metres (6ft) apart.
Relatives who do not live together are still not permitted to meet indoors, however, despite this measure being included in step one of the North’s Pathway to Recovery.
As part of the easing of the measures, garden centres and golf clubs were allowed to reopen with social distancing measures in place.