The win will be a much-needed boost for Red, coming just a month after its eight-year relationship with Samsung came to an end.
The agency had won the firm's UK press office but was pitted against awards and reviews agency Kazoo, and other outside firms, to a new consolidated brief.
The Western Europe brief is new at Huawei, created since Winston Eavis arrived as director of PR and events for the Chinese firm in May. Eavis was previously head of external comms for Europe at Samsung, where he worked with agencies The Romans and Iris, but not with Red directly.
Red's new brief includes raising the profile of Huawei Consumer Business Group (CBG) products and launches and "bringing to life the brand story", a statement said.
Eavis said: "We’re delighted to appoint an agency with the depth of industry experience and creativity of Red Consultancy. At Huawei, PR is the driving force behind all our marketing as we endeavour to earn, not buy, a place in the hearts of European consumers."
Red's blended consumer tech, lifestyle and corporate account team will led by Red Consultancy’s acting MD for its Play division, Andi Donovan.
She said: "As an agency we’ve worked with mobile brands for over twenty years and are genuinely excited by the proposition of working with the ‘next big thing’. The challenge; to increase unaided awareness and preference; is one we will meet by creating bold campaigns that cut through on creative integrity and cultural relevance."
H+K's London office, which previously ran UK PR for Huawei CBG, retains other major briefs for the brand. A spokeswoman for the agency said: "With our robust international network, H+K remains focused on Huawei’s global communications and social work that we’ve held since 2015."
Alongside Eavis, another recent addition to Huawei's comms team is Sneha Konganda, head of PR for Western Europe. She was previously at Weber Shandwick.
Red has seen a number of clients come and go in recent months; Twitter moved its brief to The Romans and Boots gave its account to Burson-Marsteller, while the firm has also bagged wins with Gumtree and Aldi.