Bunak and the Alor-Pantar languages are sometimes grouped together as "West Timor", while Bunak and East Timor have been grouped as "Timor-Kisar".
Ross (2005) believes these reflecting proto-Trans-New Guinea 1st and 2nd-person pronouns *na, *ni, *ga, *gi, and possibly the pTNG dual/inclusive *-pi-, but this has not been demonstrated to the satisfaction of other linguists, many of whom see Trans-New Guinea as a more limited family.