The increase will take place as of 20 September and will add on an extra £45 per tonne in the UK and €50 (£41) per tonne in continental Europe.

The company also said it would start negotiating with its customers over shorter payment terms.

Risto Auero, vice president, linerboards and speciality papers sales, admitted that the increases have come in fairly quick succession, but claimed prices had also collapsed very quickly during the financial crisis.

He said: "Despite these three increases, our input costs, such as raw materials, logistic costs and energy, have risen much faster than we have been able to pass them on to our customers.

"As a result, we have seen the profitability of our linerboard business fall month after month."

He added that, last month, the business unit recorded a negative financial result, despite operating its mill at maximum capacity, leaving it no alternative but to try to pass the costs onwards.

"I realise that it is by no means easy for our customers to pass the cost increases on to their customers, but there is no alternative but to press on," he said.

M-real expects the current strong demand growth for white top linerboard to moderate next year, leading to a similar moderation in price increases.