BERLIN (AP) — Germany's HeidelbergCement AG says it plans to buy Italy's Italcementi, starting with the 1.67 billion euro ($1.85 billion) acquisition of a 45 percent stake.

HeidelbergCement said late Tuesday it agreed to buy the stake from financial investor Italmobiliare for 10.60 euros per share in cash and shares. Once the purchase is completed, expected next year, it plans a mandatory takeover offer to remaining shareholders. HeidelbergCement says it expects that offer to be at the same price, valuing Italcementi at 3.7 billion euros.

HeidelbergCement shares dropped 6.3 percent Wednesday to 66.43 euros.

The German company says that buying Italcementi will add "a valuable portfolio of assets with a perfect geographical fit" to its existing activities. It says the deal will require approval by competition authorities particularly in Europe and the U.S.