The meeting is taking place in the midst of a divide in the party's legislative caucus, as six members defected in a bid to undermine the alliance with the Panameñistas.
Those dissidents helped elect PRD Deputy Rubén De León as the president of the Assembly, defeating fellow PRD candidate Crispiano Adames, who had been supported by the majority of the caucus. Upon his arrival, De Leon said that today's meeting seeks to send a clear signal to the leadership that a change is needed.
De León supporter Leandro Avila said that differences must be resolved in a peaceful manner.
"We won't fall into provocations," said Avila.
But, 100 meters from the march, supporters of current PRD President Benicio Robinson gathered wearing shirts that read, "Down with traitors."
"Out with the traitors. Benicio, here's your people," shouted the group.
At the meeting, the delegates will determine the schedule for the internal elections and adopt the rules of procedure for the 11th Ordinary Congress.