The Union's Kolkata branch secretary Dipankar Bhattacharya alleged that activists of the Trinamool Congress ransacked the venue of the meeting in front of the new administrative building.
They also stopped the workers who were coming to attend the meeting, he alleged.
The Trinamool Congress denied the allegation.
Barun Natta, North 24 Parganas district president of the party's youth wing, said the party was not involved in the incident.
"As the meeting was to be held during office hours, angry employees themselves did it," he said.
Personnel of the Airport police station came and controlled the situation.
No one was arrested.