Google acquired Nest Labs for $3.2bn (£2bn) in January this year.
PRWeek understands that the brief is focused on consumer technology. PR agency Bite currently handles PR for Nest. It is not yet known whether Bite will be reconsidered for the account.
It is understood that Nest has issued an RFP and has approached a handful of agencies so far.
The company was founded by two former Apple executives Tony Fadell and Matt Rogers and makes internet-connected thermostats and carbon monoxide and smoke detectors.
The thermostats can determine people's behaviour through room temperature and humidity, and light sensors, and can work out whether people are occupying a room or not.
Following its acquisition Nest continues under the leadership of Fadell with its own distinct brand identity.
Nest declined to comment.