In a statement the AP said it has been "holding a series of employee consultation meetings as the next step in the proposal to freeze its defined benefits pension".
"Under the proposed changes, the defined benefits program would be replaced with a defined contribution plan," the company added, affecting around 200 members of staff.
"Like other news organisations and businesses in recent years, AP can no longer offer a defined benefits programme as it moves forward amid global economic challenges and continuing disruption in the media industry."
A defined benefits programme offers a guaranteed amount upon retirement, usually based on factors such as salary and length of service, compared to a defined contribution plan which means the final amount will be based on set contributions made to an individual’s retirement account by the company and investment returns.
In a statement the NUJ claimed the replacement defined contribution scheme is "inadequate" and say their members "will suffer significantly" as a result.
"The company is not carrying out a meaningful consultation, allowing time to reach an agreement," NUJ officials Laura Davison and David Ayrton said in a statement.
"Instead it is attempting to railroad through its proposals without listening to staff."
The NUJ said it, along with Bectu, remains "committed to reaching a settlement to the dispute" and have offered to attend arbitration and conciliation service ACAS to resolve the issue.
Bectu had not responded to a request for comment at the time of writing.
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