PARIS (Reuters) – French carmaker PSA (PEUP.PA), which plans to merge with Fiat Chrysler (FCHA.MI) to create the world’s fourth-largest automaker, has called a called meeting of its supervisory board for Tuesday, two sources familiar with the situation told Reuters on Thursday.

The sources said a planned Memorandum of Understanding between the two groups could be presented to the PSA board at that meeting, but all details were not yet finalized and discussions were still ongoing, one source said.

A PSA spokesman declined to comment.