Mulberry leaves with brown spots.

Hello Chrispook
Most probably a fungus called Anthracnose and caused by the fungus Gleosporium which is bad in rainy springs. Light brown spots that then run into each other and eventually cause leaf death
If the spots are reddish brown then it could be the fungus Cercospora again thei ois bad in rainy seasons
If the spots are at first looking water soaked then t=it could be a bacterium called Pseudomonas The spots become sunken then the leavesbecome distorted and the tips wither and die
I think it will be the the fungi judging from the picture
Chemical fungicides will help if sprayed in a rainy season
1)when the leaves start to open
2)when the leaves are half open and then
3)when the leaves are full open
Burn all infected leaves
Good luck

Thanks for the advice Marhea. I will take off all infected leaves and use anti fungal treatment and pray. Interestingly our summers are usually very hot and dry but this year we had more rain than usual in Spring and early Summer, and 2 years ago we also had more rain in Spring so this fits with what you say.