The Minister for the Environment and Climate Eamon Ryan, has been cleared of Covid-19.
The Green party leader took a second PCR test as recommended by the HSE - which came out negative.
He is is now planning to travel to Scotland tomorrow to attend the Cop26 summit.
Meanwhile, negotiators at the summit in Glasgow have been urged to make ambitious commitments to tackle global warming as the conference enters its second week.
Heads of state have so far signed up to pledges to end deforestation and phase out coal.
But Ugandan environmental activist Vanessa Nakate, is demanding more action:
"The climate and ecological crisis is not just about weather patterns, or data points, or net zero targets. It's not about statistics. The climate and ecological crisis is about people, real people."
