The Labour Court is to issue a recommendation aimed at resolving industrial action at Bus Éireann before lunchtime tomorrow.
The NBRU have stated that pickets will remain in place until the recommendation is received.
General Secretary Dermot O'Leary said: "Having completed the Labour Court process, and in keeping with our commitment to the Court, Pickets will remain in place until such time as a Recommendation is received, expected to be at lunchtime Thursday."
Mr O'Leary went on to say: "Bus Éireann have displayed outright brass-neckery by attempting to paint our members in a bad light by implying that they would not cooperate with a return to work before the issuing of the Labour Court Recommendation, this despite the fact that Bus Éireann management were present at the Court when the request to lift Pickets was accepted by all five Unions.
The treatment meted out to our members by their employer, supported by those in Government and the NTA over the last number of months, is something that will live long in the memory of our members, staff at Bus Éireann, to their eternal credit, have shown tremendous dignity throughout this disgraceful attack on their family life," he said.
RTE reports that Acting CEO at Bus Éireann Ray Hernan said it was regrettable that unions had not been prepared to lift their pickets until the recommendation is delivered.
He said services are unlikely to be restored before Friday.