Workers at Virgin Media have unanimously voted to ballot for industrial action following the company's decision earlier this month to cut up to 65 jobs in an effort to improve growth.
The trade union Unite, which represents the workers, said the company failed to consult the unions involved either before or after the announcement.
Unite said it has written to Virgin Media to remind the company of its obligation to engage in a 30-day information and consultation period before issuing notices of redundancy in order to minimise job losses.
Unite regional officer Brendan Byrne said: "No redundancies should be imposed before a full consultation process has been carried with a view to minimising job losses, as required by law."
Mr Byrne also said that the redundancy packages offered to those laid off were not in compliance with the packages negotiated beforehand.
He said: "Our members have also been shocked to learn that the redundancy package being proposed by the company is inferior to that agreed with unions in 2015."
Unite has also called on the Government to intervene to avoid industrial action.
Mr Byrne said: "The resolution of this dispute lies in the hands of Virgin Media, and we would urge Communications Minister Richard Bruton to intervene."
In a statement Virgin Media said the transformation and efficiency programme is aimed at ensuring continued revenue growth in a highly competitive market.
The company said it has entered a 30-day consultation period with staff which is being conducted in a sensitive and appropriate manner.
It added that the roles impacted do not fall under the collective bargaining groups and therefore consultation with the unions is not required.
"Employee representatives have been nominated in the business," a company spokesman said.
"We are aware of and are adhering to our legal obligations."
