It is often the practice that when we meet. Congratulations on achieving agreement or with the purpose to show good intentions and probably originates from the shows that there are no weapons in hand.
It is often customary practice when met by congratulating each other. Or on agreement The objective is to show good intentions. And may have originated from the show that there were no weapons in hand.
The tradition that is often treated once met. Apart. Congratulations, or when the agreement is aimed to show the good intentions. And may have originated from the show that in hand, no weapons.