Nippon Sheet Glass doubled its Pilkington stake

He said a merger between the two firms was not on the agenda, but added it was still possible that NSG could join Pilkington's board.

"It is something that we would like to keep open," Scaroni told reporters.

Scaroni was also bullish over the prospects for the company's self-cleaning glass product, called Pilkington Activ. He said the product would contribute "significantly" to underlying earnings from the next financial year onwards.

He added that Pilkington did not plan any major job cuts to cope with falling demand. The company has cut over 12,000 jobs in the last four years to save costs and improve results.

Earnings per share before exceptional items rose 21 percent to 5.1 pence. The interim dividend was maintained at 1.75 pence.