Question

How do countries come to diplomatic agreements—and what happens when two nations cannot reach a diplomatic agreement?

Answer 1

Like all agreements, two parties talk, say what each side needs and discover they have shared conviction, so make the understanding in composing.

In the event that they can't achieve a conciliatory understanding, they talk, say what they need and have no shared opinion, so nothing gets signer.

It is the same in business contracts. Once in a while parties can talk for quite a long time or decades without going to an agreement or reaching a final decision.