Global travel agency Thomas Cook Group PLC (LON:TCG) said Wednesday it will slash its British and Irish workforce by 2,500 as it struggles to adapt to competition from online travel sites by cutting costs.

The 171-year-old London-based company said it will cut by its payroll 16 percent in U.K. and Ireland and close 195 of its 1,069 offices in those countries, where it employs 15,500 people. About 900 of the 2,500 positions being eliminated are administrative or managerial.

The staff reductions are part of the company's three-year restructuring plan to adapt to a market increasingly dominated by Internet-only services that let tourists book their own vacation travel and related activities. The turnaround plan aims to reduce costs in the U.K. business by £140 million ($211 million).

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