What is the cause if this coolant leak?

Am struggling to identify the location of this slight coolent leak (blue) on my 300tdi Defender (see picture). Any ideas where this is likely to be coming from? The P gasket at the top looks dry. Is it just time to change the water pump and p gasket and be done with it or should I be looking for something else? It's not a big leak at all but increases more on some days than others for some reason. Thanks.

I had the same leak for a few months and it really did my head in. It turned out to be the water pump gasket. I had changed a P-gasket without removing the water pump and probably disturbed the water pump gasket when i undid the 3 bolts that go through the P-gasket and into the block. I never really knew whether it was the gasket or the pump because i broke the pump when re-assembling so I had to change it.

Thanks. I think I'll just change the water pump and the p & waterpump gaskets and be done with it. Thanks.

Yep, looks like P gasket to me. looks exactly like mine when the P gasket went.

I fitted a genuine one, made of tin off fleabay - was cheap, and has done the job. there's a good vid on youtube showing them both being done if that helps at all....