Ending trade ?

[Citizen W]

I have hunted through the manual and all I can find is that a trade agreement is supposed to come up for renewal in 20 years, but it seems this is only if the AI wants it to. My last game (first win-diplomatic!) I had to trade my ivory and silks early for saltpeter and then coal, instead of wining my people and showering them with jewels. I must have bought that saltpeter somehow because it never came up for rebid. Coal did several times, but after I finished my rail network and was ready to ditch the deal, I never in another hundred years got the chance.

Is there a way to take the initiative, is this a bug, or what is up? Thanks

[Grunthex]

Open diplomacy. Propose a deal. Click the "Active' Button below the trade window to show your current deals. If there is no number next to a deal, you can cancel it by clicking on it. Actually, that re-proposes the deal, but then you say never mind.

If there is a (Number) next to the deal, that his how many turns it is still enforced for, the only way to cancel it is to declare war.