State A has a bilateral agreement with State B, which provides for the reciprocal freedom of movement between their nationals in their respective territories.

In application of this agreement, many nationals of State B have moved to Staate A, which is a rich, well-resourced state. Additionally, State A has granted the authorities of State B, access to its territory for the use military of exercises.

After several years the relationship between the two (2) States deteriorates, leading State A to denounce the existing bilateral treaty and expel all nationals from State B living in State A.

In response, State B, initiates proceedings before the International Court of Justice (ICJ) claiming that State A has violated their bilateral treaty, customary law and the general principles of good faith and pacta sunt servanda. However, State A has made a reservation excluding the application of any bilateral treaty binding upon the parties in the dispute.

What issues of international law will the International Court of Justice (ICJ) need to consider in this scenario?