Microsoft and Facebook have agreed to jointly build a subsea cable across the Atlantic Ocean to meet growing demand for high-speed cloud and online services.
The construction of the new "MAREA" cable will begin in August this year and it is expected to be completed in October 2017, the companies said in a statement.
MAREA will span 6600 kilometres, and is the first cable to connect the United States with southern Europe. It will be operated and managed by Telefonica's telecoms infrastructure unit Telxius.
The cable is initially designed to carry 160 terabits of data per second.
The new cable venture comes nearly two years after Google agreed with five Asian companies to invest about US$300 million (A$416 million) to develop and operate a trans-Pacific cable network connecting the United States to Japan.
Microsoft declined to disclose the financial details about MAREA, but the company said last year it had embarked on a large-scale program to invest in subsea cables to connect its worldwide data centres.
Before MAREA, Microsoft has also been experimenting with underwater data centres under its Project Natick, and last year tested a prototype on the seafloor for four months.
Underwater data centres, envisioned to be powered by renewable marine energy sources, are expected to reduce the huge cost associated with cooling data centres that generate a lot of heat, and also to reduce the distance to connected populations.