United Parcel Service launches its 5.16 billion euro ($6.6 billion) cash bid for Dutch rival TNT Express Friday in a major expansion of its presence in Europe's package delivery market. 

The offer period for the 9.50 euro ($12.06) per share bid runs through Aug. 31 “unless extended,” the two companies said.

UPS reiterated it is seeking support from at least 80 percent of shareholders in TNT Express, whose executive and supervisory boards backed the offer that was tabled on March 19.

TNT Express, which was spun off from Dutch mail operator Post NL last year, will convene an extraordinary shareholders meeting on Aug. 6 to brief investors about the deal. Post NL is tendering its 29.8 percent stake.

UPS sought clearance from European Union regulators last Friday for the biggest acquisition in the U.S. firm’s 105-year history.

The EU will decide by July 20 whether to wave through the deal or begin an in-depth investigation that could result in concessions from UPS.

UPS denied reports it has offered to divest TNT Benelux or its German operations to meet any EU objections to the takeover.

Kurt Kuehn, UPS chief financial officer, has expressed confidence the deal will get regulatory approval by the third quarter.

“The transaction will create a global leader in the logistics industry with more than $60 billion in annual revenue and an enhanced, integrated global network,” the companies said.

UPS said merging the two companies would produce annual pretax cost savings of $510 million to $710 million after four years.

TNT has a leading 18 percent share of the intra-Europe express market. Germany’s Deutsche Post DHL has a 16 percent share; UPS, 14 percent; and FedEx, 5 percent.