The chief medical officers in Northern Ireland and the Republic will sign a Memorandum of Understanding formalising co-ordination and co-operation between the Irish Government and the Northern Ireland Executive this week.
It comes as Tanaiste Simon Coveney held a teleconference with Secretary of State Brandon Lewis and Stormont's leaders to discuss ongoing co-operation to deal with coronavirus.
In a statement following the meeting, deputy First Minister Michelle O'Neill said the Covid-19 pandemic "does not respect borders".
"Co-operation and common action across our island is vital at this time," she said.
"Protection of the lives and welfare of everyone on the island is paramount, and no effort will be spared in that objective.
"Working closely together, the two chief medical officers will sign a Memorandum of Understanding formalising co-ordination and cooperation between the Irish Government and the Executive this week."
"We need to be agile, open and have close and ongoing contact with frequent meetings of all those who met today, and a fortnight ago in Armagh to do our absolute level best to save lives and protect public health of everyone on this island."
On Monday, Arlene Foster and Ms O'Neill acknowledged they are at odds on certain coronavirus issues, but insisted they are united on the main goal of saving lives.
The First Minister and Deputy First Minister said differences of opinion should be expected within a five-party coalition government.
They made the comments following reports of growing tensions around the executive table over issues such as testing numbers, personal protection equipment stocks and closure of non-essential businesses.
Earlier this month, the two main executive parties, the DUP and Sinn Fein, were also divided on when schools should close.
The Republic and Northern Ireland have agreed to cooperate on a number of measures including the joint order of the personal protection equipment from China.
