German copper producer Norddeutsche Affinerie expects to complete the takeover of Belgian peer Cumerio in mid-April, the company said in a statement. The purchase of 95 per cent of Cumerio's shares will create Europe's largest copper corporation.

Cumerio is among the largest investors in Bulgaria, operating a copper-processing plant in Pirdop, 50km east of Sofia, through its Bulgarian subsidiary, Cumerio Med.

Norddeutsche Affinerie first spelled plans to become majority shareholder of Cumerio in June last year. Then it said it was ready to pay $1 billion (640 million euro) for raising its stake in the Belgian company from 30 to 95 per cent. The German company is expected to pay the sum 15 business days after signing the agreement.

The merged company will have annual output of one million tonnes of cathode copper and will keep 4 600 officials on the payroll. The two companies have production facilities in Bulgaria, Belgium, Germany, Italy and Switzerland.

Copper, widely used in the power and construction industries, has seen its price go up fourfold since 2002.