The group currently produces more than 5m magazines a week for DMG Media’s Daily Mail and Mail on Sunday.

These include Weekend magazine for the Daily Mail’s Saturday edition, and Event and You magazine for the Mail on Sunday.

The Daily Mail on Saturday had a circulation of 2.2m in the latest ABC report, with the Mail on Sunday’s circulation 1.4m.

The publisher has made no comment on the situation since Polestar’s pre-pack sale a month ago.

Last week Polestar chief executive Barry Hibbert told PrintWeek that that 39 of 42 key clients had signed new contracts with the group.

Speculation is now rife that DMG is yet to novate its arrangement to the ‘new’ Polestar and could even move its giant contract abroad, or take some of the work in-house and use its own presses.

Polestar won the then-Associated Newspapers contract in 2005, and it was the first major win for the group’s brand new gravure site at Sheffield.

The DMG titles are currently printed gravure and web offset at Polestar Sheffield.

A source said: “The word on the street is that they haven’t signed [a new contract]. Let’s face it, anyone who prints with Polestar has got to have a Plan B or a Plan C – you just have to. It will be extremely interesting if they don’t stay.”

Until they moved to Polestar in January Express Newspapers printed its supplements on the continent at Roto Smeets, while the Telegraph Media Group used to print some of its supplements at Germany’s Gruner + Jahr (now Prinovis).

PrintWeek could not reach Hibbert for comment at the time of writing.