United Parcel Service Inc. has agreed to buy TNT Express with a bid of 5.16 billion euros ($6.8 billion), the biggest purchase in the U.S. company’s 105- year history, to challenge Deutsche Post AG (DPW) in Europe.

TNT accepted an offer of 9.5 euros a share in cash, the companies said in a joint statement today. That’s 5.6 percent more than the 9-euro bid turned down last month by Hoofddorp, Netherlands-based TNT and 54 percent more than the closing price on Feb. 16, the day before the talks were made public.