Shares in the company fell as much as 4.6 percent to 925.5 pence, making them the largest percentage losers on the FTSE 100 <.FTSE> on Friday morning.

The company, which has issued a string of profit warnings as it struggles to cope with a downturn in its biggest markets, said underlying sales fell 7 percent to 1.87 billion pounds ($2.47 billion) for the six months to June 30. This was worse than a 5 percent fall forecast by a company-provided analyst consensus.

Political and economic strife have combined to derail its plans to sell text books and mark exams in the United States, its biggest market.

In response, Pearson unveiled a restructuring programme and said it would cut 4,000 jobs, or more than 10 percent of its work force. The company said on Friday about 3,450 employees had been notified of their exit.

Pearson said it remained on track to deliver its guidance for the full year, and added that currency exchange rates could boost its earnings per share guidance range by 4 pence if they stayed at their current levels.

The company's previous earnings expectations were between 50 pence and 55 pence for the year.

(Reporting by Esha Vaish and Soumithri Mamidipudi in Bengaluru, Kate Holton in London; Editing by Gopakumar Warrier)