HTC is expected to reveal its official partnership with the social networking site at the Mobile World Congress event in Barcelona next month, according to City AM.
The two new “high-end” smartphones are thought to have Facebook branding and colours and are understood to run on a version of Google’s Android operating system adjusted to display Facebook notifications and messages more prominently.
It is also expected that users will be able to call or email friends directly from information stored on Facebook.
An HTC spokesman says: “We do not comment on rumours or speculation.”
It has long been rumoured that Facebook is set to launch its own-branded handsets, but the social network has always denied reports suggesting it is developing its own phone.
HTC is currently bolstering its UK commercial team and the appointment of a new UK marketing director is expected to be announced imminently.