The U.S. Nexus 6P supports FDD-LTE (the standard used here) and bands 2, 3, 4, 5, 7, 12, 13, 17, 25, 26, 29, and 30. Our telcos all use band 3 and 7, so the U.S. set will work here just fine. That said, Singtel also uses band 8, for tri-band carrier aggregation (CA), but it doesn’t really matter, because the Nexus phone is a Cat 6 device supporting dual-carrier CA.
Speaking of LTE Advanced and carrier aggregation (i.e., combining channels or carriers to achieve higher LTE speeds), note that the U.S. sets can’t do CA with any of the bands we use here. In short, expect 4G speeds but not ‘4G+’ speeds.