Cutting a large plastic water butt in half

I have an old 200 liter plastic water butt which I'd like to cut in half and use the lower half as a large tub. It's like this:

Cloudburst 200L Litre Water Butt Kit | Water Saving | EvenGreener - EvenGreener

it has a 5 inch vertical split down one side which I've tried to repair many times using many methods but none have worked so it's time to put it to another use.

Not really sure of the best way to cut it though. A jigsaw is perhaps the best option but I don't have one. Maybe a wood saw?

 

An ordinary wood saw would do it.
Just one of those hard point disposable ones.

 

Thanks for the suggestions, good point about sanding the edge afterwards.

I did have another idea - use a Dremel. However, with the tiny cutting disc it would perhaps take a long time ......

 

It will take minutes with a saw, as you say I normally would use a jigsaw, I dont think those types of barrel are particularly tough.

 

Thanks, just done it using a wood saw.