Interior Minister Roni Bar-On called on Attorney-General Menahem Mazuz on Sunday to open an investigation against three Arab MKs following their weekend trips to Syria.
Bar-On said Knesset members Jamal Zahalka, Wasil Taha, and Azmi Bishara - all from the Balad party - were in violation of the law when they left for Syria without the proper authorization.
"All the requested steps must be taken in order to find justice with the three MKs, and to stop this shameful phenomenon," said Bar-On in the petition.
The MKs met with Syrian and Palestinian officials in Damascus on Saturday, in defiance of an Israeli ban on such visits.
During a meeting with members of the leading Baath party, Bishara warned Syria that Israel may attempt a surprise offensive: "Israel could launch a preliminary offensive in more than one place in a bid to overcome the internal crisis in the country and in an attempt to restore its deterrence capability."
Balad reported that the visit to Syria was intended to maintain the party's connection with the Arab world.
During an interview the Syrian news agency SANA, Bishara declared: "We are Syria's allies and will continue to be in contact with it on the national level, through our well-known views."
Syria is still technically at war with Israel.
Visiting an enemy nation is a violation of Israeli law.