Drive around town and you're guaranteed to run into at least a few signs encouraging Saigonese to keep things xanh – sạch – đẹp, or green, clean and beautiful. The city sidewalks, however, hold more than their fair share of rubbish. If you're a foreigner, it might not be a great idea to point this out, as American singer Kyo York recently discovered.

According to Thanh Nien, the singer posted a Facebook photo on August 30 commenting on the country's littering problem. In the picture, York stands outside a local pagoda with a sign that reads “Please don't leave rubbish here”. At his feet lay a pile of garbage.

“Most people seem to be saving their awareness and civility for social networks,” he wrote.

The backlash that followed was swift and, at times, harsh. While some agreed with the singer, many did not appreciate his comments, suggesting that his criticism was “digging up bad things about Vietnam” and that he should instead “shut up and go back to the US”. The most incendiary comments implied that Vietnam ought to be teaching the United States how things work and not the other way around.

The next day, York responded with a follow-up of the initial post, this time paired with a photo of littering at a national park. “If Vietnam does not have robbery, murder and terrorism, that's wonderful,” he wrote. “But that doesn't mean people have the right to ignore public hygiene.”