Digital freight firm Sennder has agreed to buy the European logistics operations of its U.S. rival C.H. Robinson in a deal set to double its revenue to 1.4 billion euros ($1.5 billion), the German company said on Tuesday.

Sennder, which brokers freight loads to freight forwarders via its online platform, hopes to optimise its connecting journeys with the larger size. "This makes us more attractive for small transport companies as well as shippers across Europe," Sennder's Chief Executive David Nothacker said.

The firm, which according to its website is backed by private equity investors Baillie Gifford, Accel and HV Capital, has operations across Europe, including in the Netherlands, France and Poland.

The acquisition of C.H. Robinson's European Surface Transportation (EST) operations was expected to close in the final quarter of this year, Sennder said in a statement.

"The transaction will be settled entirely in cash. We have agreed not to disclose the purchase price," Nothacker told Reuters. Sennder would continue to examine new opportunities in the coming months, he added. "We want to continue to invest, we want to continue to grow, we have big plans."

The company does not currently plan a new financing round, Nothacker said. About a year ago, the company had raised more than $350 million.

(Reporting by Hakan Ersen in Frankfurt, Writing by Rachel More, editing by Kirsti Knolle)