You are suppoed to be able to end a trade relation after like 20 turns. I gave the Chinese saltpeter so they could go help kill our mutual enemy. Now I wanna take it back (cause he wont gimme any oil) and I cannot figure out how. It doesn't seem intuitive if there is some way. I did cursory look through the manual and didn't find anything. Worst case scenario is that I go take his oil rich cities...but I would like to see if I could and trade him for it.

This interface at times seems a bit underdeveloped.

Thanks for any help.

Under the lets make a deal choice during diplomacy there are multiple possible options at the bottom. One says "New" and this is where it start by default. It allows you to add/delete goods for trades. Next to "New" is "Active". This is where you change active trades. Next to the trade there will be a number that says how long you have left in the agreement. This is where you cancel deals. It was very hard to find.

Thanks a ton!!!

I was going nuts last night trying to figure that out. It was getting late, but it bothered me.

Again..thank you very very much.

As a last resort, you can declare war.