Group operating profit is expected to be in the range of 160 million pounds to 170 million pounds for the full year, the company said, compared with an operating profit of 185.2 million pounds a year earlier.

Mature year-to-date revenue to Sept. 30 was down about 1.9 percent at constant currency, the Switzerland-headquartered company said in a statement on Thursday.

Short-term costs are also expected to rise as the company looks to maintain investment in its national networks, it said.

Shares of the company were down 33.5 percent at 212.1 pence by 0802 GMT on the London Stock Exchange.

(Reporting by Sanjeeban Sarkar in Bengaluru; Editing by Amrutha Gayathri)