The Malta Dockers' Union (MDU) claimed that only a small number of port workers were following the rival General Workers' Union's directives at the Freeport.
A government spokesman described the directives as "schoolyard bully behaviour" after the union refused to lift its action despite losing recognition.
MDU president Joe Saliba said yesterday the directives were being followed by 43 of the 370 port workers.
GWU general secretary Tony Zarb denied the claim, insisting that the majority of the workers were following the directive. However, he would not give a figure when asked.
On Thursday, the Malta Freeport officially granted recognition to the MDU as the main representative of its port workers after the Director of Industrial Relations completed a verification process. The MDU has 327 recognised members, according to the exercise.
The GWU refused to accept the result and described it as tainted. It said the directives it issued on Wednesday afternoon for port workers to go slow, work to rule and take their break all together, would stand.
The spokesman for the Transport Ministry said the GWU's actions gave trade unionism a bad name and left its democratic credentials in serious doubt.
Through the directives, the union was imposing itself on the majority of workers who did not recognise it and still forged ahead with illegal industrial action, he said when contacted.
"From the economy's point of view this is an unacceptably expensive way of indulging in an ego trip." The union's schoolyard bully's behaviour was especially harmful to the Freeport employees and the many businesses that depended on them, the spokesman added.
The president of the Malta Employers' Association, Pierre Fava condemned the GWU's industrial action and called for it to be declared illegal.
The employer had been drawn into industrial action even though it had no dispute with either of the unions involved and this would have repercussions on the Freeport and on businesses, Mr Fava said.
The situation, he added, highlighted irregularities. The Employment and Industrial Relations Act should lay down clearly what would happen in case two unions disagreed or if the employer were dragged into the situation.
The Freeport is holding the GWU responsible for all damages after it had "in an illegal and abusive manner" ordered industrial action at the port.
On Thursday, the court imposed a €1 million garnishee order on the GWU at the request of the Freeport. A garnishee order is used to force payment from a third party that either holds money belonging to the debtor or owes the debtor money.
The GWU said the garnishee order had effectively frozen all its assets and described the action as irresponsible. "The GWU can only conclude that this garnishee order is aimed at forcing it to stop its industrial action," the union said.
It said the Freeport's request violated trade union immunity as granted in the Industrial Relations Act within the context of industrial disputes.
The GWU executive council met yesterday morning with the union's workers committee to discuss the situation. The union had no choice but to reply to the attack and would discuss the matter with foreign trade unions, Mr Zarb said when contacted.
He pointed out that the union had always informed industrial relations director Noel Vella that it had never agreed with the system by which union recognition was granted.
The union had commissioned a secret ballot of the workers, conducted independently by law professor Ian Refalo, which found it enjoyed the support of 53 per cent of port workers. When the union announced this result, no one contested it, Mr Zarb said.
However, Mr Saliba pointed out that all the GWU had to do was present Dr Vella with all the relevant documents after their "so-called independent poll" claimed they represented the majority: "This is the only way they can contest his decision". The dockers' union itself had presented Dr Vella with all the relevant documents to prove they were the main union: "Our books are open," he said.