he DUP has been accused of “obstructing” north-south institutions.
Sinn Fein and the SDLP say the DUP failed to nominate a unionist minister to attend two North South Ministerial Council (NSMC) sectoral meetings in recent weeks which prevented them from going ahead.
Alliance leader Naomi Long added her criticism, describing the situation as “simply unacceptable”.
One accompanying minister from the opposing political view must attend NSMC meetings to allow them to proceed.
On Friday, Infrastructure Minister Nichola Mallon (SDLP) said an NSMC transport meeting could not go ahead due to no unionist minister having been nominated.
DUP leader Arlene Foster later claimed the meeting did not happen due to a timing issue and insisted it would take place in the future.
Sinn Fein Communities Minister Deirdre Hargey said an NSMC languages meeting was cancelled on March 31 because a unionist minister was not in attendance.
The PA news agency understands that Ms Hargey wrote to the Stormont Executive earlier this week to express her disappointment at the situation.
Ministers discussed the matter under the any other business section of Thursday’s Executive meeting.
It is understood that deputy First Minister Michelle O’Neill has asked the head of the civil service to ascertain if all ministers are continuing to participate in north-south ministerial structures.
The next scheduled NSMC sectoral meeting is set to take place on April 28 and will concern agriculture.