Johnston Press, owner of newspapers including The i and The Yorkshire Post, saw its shares tumble by more than six per cent this morning as it released an update to the City ahead of its AGM.
Revenues for the year so far were down nine per cent on the same period last year, Johnston said, despite "continuing strong performance" from The i.
The news business also blamed the EU's new General Data Protection Regulation (GDPR) for hitting its advertising revenues, since restrictions around how advertisers can now use customers' personal data to target them online has caused many to hold back.
"The trading environment remains extremely challenging, exacerbated in recent months by uncertainty around future paper costs and the impact of GDPR on digital advertising revenues," said Johnston Press in a statement.
"We expect to see continued pressure on revenues in the second half of the year, and a requirement for cost savings."
However, the company added that it expected its results for the full 2018 calendar year to be in line with expectations.
Johnston also updated on its debt refinancing talks, after it revealed it had begun a strategic review last year to assess how it would pay back £220m of bonds due in June 2019.
The firm said it was in talks with a committee of the bondholders, the largest of which is US hedge fund Goldentree, about "potential amendments to the group's pension scheme".
However, Johnston added that no agreement on these amendments had been reached and that any proposal would be subject to the consent of "relevant stakeholders".