The literal meaning of "là" is "there": it contains the idea of pinpointing a more or less distant place. With language evolution, it becomes often substituted from "ici" ("here"), for example:
Tout le monde est là, nous pouvons commencer la réunion.
To pinpoint a temporal instant you can also use "là", but "ici" looks very old-fashioned, even if you are talking about here and now:
Voilà le plan: on s'infiltre par la cheminée, on attend que les parents s'endorment, et là on ouvre la porte ! (and then we open the door!)
-Essaie ce coussin. -J'ai toujours mal au dos. -Et si tu rajoutes une couverture ? -Là ça va mieux. (now it's better.)
Concerning your example, "là" is about a temporal pinpoint: it makes a link to the temporal localization of the negotiation. In this sense it is an emphasis.
You can use this emphasis in other sentences when you have this motivation about remembering the importance of the localization. It could be because the order of the actions is important (like if you are giving instructions), or because you want to emphasize the emergency of the present situation, or even (as it could be the case in your example) to remembers about the fact it won't last long so there is no need to worry.
There can be an ambiguity between if it is a spatial or temporal localization, so be careful about that. For example:
Elle entreprit un voyage vers la ville de XXX. Là elle croisa un vieil ami.
Could mean she encoutered an old friend at XXX, or while traveling to XXX. The first meaning sounds more natural, but the second is technically correct too.