Oil leaking from exhaust tip

My 2011 Prius with 140K miles on the clock is dripping what appears to be oil from the exhaust tip

The oil drips in small amounts and only when the engine is on.

I had a problem a few days ago with the heat shield so I removed it. There was also a bracket holding on to the exhaust pipe which was rattling against the exhaust pipe. It look corroded so I removed it.

Any thoughts here?

 

I have been monitoring this over the past week.

The liquid coming out of the tail pipe appears to be water. It is transparent and doesnt feel oily. The liquid is only produced at the end of the warmup stage (S1a)

I also ran an experiment where I put a drop of water from a water bottle on the concrete when the tail pipe produced the liquid. Both the water and the liquid from the exhaust disappeared at similar times. If it was oil I would expect it to stay on the surface for longer than water?

The oil levels have remained consistent over the past week.

The temperature in the UK has been changing a lot recently. We have cold mornings (-1) and reasonably hot afternoons (18). I leave the car running throughout the day. Could this be the reason for the water produced out the tail pipe? Would this add more water to the combustion process?