Mecom's share price has plummeted by a third in early trading, after the beleaguered European publisher issued a profit warning.

Mecom, which was formerly run by ex-Mirror Group chief David Montgomery, shocked investors admitting that ad revenues will plummet more than 20% in March and April.

Last month Mecom reported a loss of €30.4m (£25.9m) and revealed that ad revenues at its flagship Dutch operation, Wegener, had fallen an eye-watering 28% in January and February.

Mecom's share price fell 33% to 55.88p in early trading on Monday, as investors took fright at the trading update.

While an improvement over the horrific start to the year, investors are particularly concerned at the rate of decline given it includes the usually advertiser-friendly Easter trading period.

Mecom said that earnings, before interest, tax, depreciation and amortisation – broadly operating profit – in March and April have fallen behind last year's levels and the outlook for the rest of the year looks grim.

"The Dutch economic crisis has worsened, with new data published at the end of March showing deteriorating trends for a number of indicators," the publisher said. "The depth of the crisis is expected to affect advertising revenues for the foreseeable future and any improvement in economic conditions and consumer confidence is not anticipated until later in the year at the earliest."

Mecom said that if the pattern of advertising declines seen so far this year continues revenues at its Dutch business will fall "significantly short" of expectations well beyond what it might be able to claw back in cost-cutting. "Taken together, therefore, if the adverse pressures described above do not reduce considerably from current levels, group [profits are] likely to fall materially short of current market expectations."

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