Business Minister Heather Humphreys has said high rates of Covid-19 in Co Cavan and Co Monaghan are not linked to people crossing the border.
A report covering data up until last Friday shows Co Cavan has an incidence of 753.5 Covid-19 cases per 100,000 of population compared with 684.6 in Dublin.
There is a similar pattern in other border counties, with Monaghan at 570.2 on Friday, while Co Louth rose to 463.2.
Ms Humphreys, a TD for Cavan and Monaghan, told Virgin Media News: “The level of infection in Cavan and Monaghan has nothing to do with people coming from across the border.
“In fact, there were four residential nursing homes that had outbreaks plus there were also outbreaks among the staff in Cavan General Hospital.”
Two weeks ago, a number of doctors were sent from Dublin to Cavan General after an outbreak of Covid-19 among staff increased pressure on the hospital.
“There is also increased testing in residential healthcare settings which is adding to the numbers,” Ms Humphreys said.
“To be clear, there is no evidence whatsoever to suggest it has anything to do with people travelling over and back across the border.”
On Tuesday, 20 further deaths as a result of Covid-19 in hospitals in Northern Ireland were reported – the biggest single daily increase since the outbreak began. It took the total in hospitals in the region to 329.