Turning around tension

Where I live, one part of each train is reserved for working. Loud talking or phoning is forbidden.

So anyway, two girls come and sit in the seats on the other side of the aisle and start chatting with the guy that's sitting there. As a matter of habit, I ask them to be quiet. They do so, but one of the girls apparently is slightly belligerent and starts chatting again. She kept an eye on me and she made some remarks to the guy, remarking on my request.

I felt like there was some negative Tension there. But it's tension nevertheless. Any ideas on how to turn around negative tension?