In the May 12 referendum, voters will be asked to decide whether to allow dual citizenship to citizens of countries meeting "Euroatlantic integration criteria", with a list of such countries to be set by a law.
Currently, people who left Lithuania after it regained independence in 1990 cannot hold dual citizenship, apart from a few exceptions. That provision can only be amended by referendum.
Lithuanian expatriates fear that the dual citizenship referendum might fail due to low turnout as approval from more than a half of all eligible citizens, or around 1.3 million people, is needed to amend the article of the Constitution.
Rimantas Baltaduonis of Washington, D.C., who chairs the joint commission, says the nation must mobilize for the referendum, because it is unclear if it will "ever have a second opportunity of having one's say about (allowing one) to retain their citizenship of the Republic of Lithuania after acquiring the citizenship of another state".
Wednesday's discussion on dual citizenship is expected to be attended by former President Valdas Adamkus, Viktoras Pranckietis, the speaker of the Seimas, and Vilnius Archbishop Gintaras Grusas.
The commission of the Seimas and the LWC normally meets twice a year.