"It's beautiful, isn't it?" Putin said in Obama's general direction as they walked into the room.
The two leaders and their aides had clearly agreed it wasn't in their interests to completely ignore each other, but Obama was in no mood to clap the Russian leader on the back.
Putin hasn't complied with the world request that he withdraw troops from Ukraine, where Russian-backed separatists continue to move in the east and a cease-fire agreement appears to be faltering.
Their awkward exchanges did not go unnoticed.
At the opening plenary session on Tuesday, the rest of the world leaders noticeably hung back and let their host, Chinese President Xi Jinping, handle the contentious pair. They walked in as a group, with Xi at the lead and Obama on one side and Putin on the other. `
Putin was the one to reach out with the "isn't it beautiful" pleasantry, and, as the two went to take their seats, he reached out to clap Obama on the shoulder.
As the day went on, the Russians were spreading word about the contact, with the Kremlin spokesman telling reporters the pair had spoken "several times."
The White House downplayed the interactions, waiting until late in the day to acknowledge that, yes, on three occasions, for a total of about 15 to 20 minutes, the men had spoken.
News cameras at an afternoon tree-planting on the Yanqi Lake grounds followed Obama and Putin as they prepared to "plant" the evergreen trees representing their nations' participation in the 2014 summit. (In reality, each leader simply shoveled a few lumps of dirt onto the base of his already-planted tree.)
"Hey, hombre!" he shouted, waving, before resuming his cool detachment.
"Success!" he joked to another leader, as they turned to go inside for more meetings.