Ballot papers will be issued to members this Thursday at all 12 Trinity sites across the UK questioning whether action should be taken and, to what extent, with strike action one of the possible outcomes.

Most of the sites affected are the print centres for the Daily Mirror, but all other sites, including the Canary Wharf headquarters will also be balloted, the union said.

According to Unite national officer Steve Sibbald, the action is against the "unilateral imposition of the wage freeze".

When it was announced in November, all of the company's sites were told they faced a freeze, regardless of performance.

However, in the past, Unite chapels have negotiated independently and often pay increases have been based on site performance.

Sibbald told PrintWeek: "In the past when we tried to negotiate nationally, Trinity has insisted that each site stands on its own merits and each site was rewarded according its own performance.

"So when the board decided on a wage freeze for all it went against everything we have been told over the past 15 years. Some of the sites were losing money yes, but some were profitable. If they are going to freeze nationally, we will respond nationally."

If the members vote for industrial action, Unite has 28 days to take action, however, it would expect to carry out the action within a week or two weeks of the ballot. Sibbald said that Unite would want to sit down with Trinity before any action is taken.

He added that the reason the ballot has take place so late in the year is down to the difficulty getting 1,100 staff organised for a ballot, coupled with the fact that the anniversary dates differ at each site.

He also said that it was a new position for him to be in, as negotiating with newspaper publishers had previously taken place on a regional level.

"One site and chapel is easy to turn around, you can do that in a week," he said. "But when you have 12 sites, 28 chapels and God knows how many occupations, it can take a while. We have never dealt with a publisher on a national level before so we are in unchartered waters here."

A Trinity Mirror spokesman said: "We're disappointed that Unite is seeking to take this action, particularly as it's now nine months since the decision not to hold a pay review was announced.

"The decision was taken as part of a package of cost-reduction measures designed to ensure that we survive the dramatic revenue and profit downturn. Unite's actions will not deflect us from that goal."