Williams’ former title sponsor At-and-T has switched allegiance to reigning world champions Red Bull.
The American multinational telecom became Williams’ naming backer in 2007, but left the Oxfordshire based team after its dire 2011 campaign.
Red Bull announced in Monaco that the company has now joined the Austrian energy drink-owned team as an official technical supplier.
"Red Bull Racing is excited to work with an innovative, global and reputable brand such as AT-and-T," said team boss Christian Horner.