Takeda, Japan's largest drugmaker, said on Friday it has not agreed to buy Swiss rival Nycomed, following reports it was in talks to buy the privately held company for more than $12 billion.

Such a deal would boost Takeda's global reach into Europe and emerging markets.

"The company would like to make clear that Takeda has not agreed to any such an agreement as suggested by certain newspaper publications," the group said in a statement on its website. "Takeda is constantly seeking and evaluating opportunities to increase shareholder value and enhance our business through strategic investment; however, there is nothing that needs to be announced at this point," Takeda said.

A person familiar with the matter told Reuters that a deal, which would be Japan's second-biggest overseas takeover, was in its final stages but might take time to conclude.