Ní Raghallaigh, who also works as a teacher, is taking annual leave to take part.
Kildare South Sinn Féin TD Shónagh Ní Raghallaigh has said that as an Irish Republican she knows "what it means to resist colonial violence and fight for dignity" as she prepares to join a protest flotilla bound for Gaza.
Ní Raghallaigh, who has also worked as a teacher, is taking annual leave to take part.
She said the mission is a "civilian effort to break the siege of Gaza".
Ní Raghallaigh compared the move to her own Republican background, saying she knows what it means to "fight for dignity".
She also declared that Republicanism is "about action" and that it is time to stand in "solidarity" and in "struggle".

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