Pit viper

"In a revision by Vogel et al. (2007) the Tropidolaemus wagleri species complex was differentiated into several taxa, including the resurrection of T. subannulatus. The Western Philippine populations belong to T. subannulatus, but those from Mindanao include snakes assigned to both this species and T. philippensis. Tropidolaemus subannulatus has a wide distribution in Central Indonesia, Malaysia and Philippines, T. wagleri is restricted to mainland Southeast Asia, down to Sumatra and Bangka, West Indonesia. T. subannulatus will be split further in the future (G. Vogel pers. comm. September 2011)." http://www.iucnredlist.org/details/192241/0

@alicelongmartin: It would much prefer to slide away over attacking and risking being killed. And it did not look cornered to me.

I would suggest it is highly poisonous and you need to keep your distance.