Saeed Mirza, Lebanon's prosecutor-general, has received the court summons for Walid Jumblatt, a Druze member of parliament, and two other men, but has yet to formally notify them, a procedure that can weeks or months.
The US on Friday condemned the issuing of the summons. "These actions are cynical attempts by the Syrian government to continue its interference in the Lebanese political process," State Department spokesman Sean McCormack said.
"These actions must come to an end now."
Hossam al-Deen Habash, a Syrian attorney, who launched the lawsuit against Jumblatt, said in Damascus on Saturday that once the three have been formally notified of the summons, they have a week to appear before the Syrian court.
Otherwise, they face "arrest warrants and trials in absentia".
"If Jumblatt fails to appear before the court, he will be tried in absentia," Habash said.
"I personally filed the lawsuit against Jumblatt because he incited a foreign country (US) to occupy my country," Habash told The Associated Press in Damascus.
In an interview with the Washington Post newspaper in January, Jumblatt responded to a question about what he wanted from the US, saying, "You came to Iraq in the name of the majority. You can do the same thing in Syria."
Habash described Jumblatt's comment as a "a criminal provocation".
"These provocation and incitement calls are punishable under (Syrian) law even though the (called for) action was not carried out," Habash said.
The Syrian military court has also summoned for questioning Jumblatt's top aide, Marwan Hamadeh, the Lebanese telecommunications minister, and anti-Syrian journalist Fares Kashan for allegedly "defaming" Syria by holding it responsible for last year's assassination of Rafiq al-Hariri, the former prime minister, and a string of bombings that targeted anti-Syrian figures in Lebanon.
A UN probe has implicated senior
Syrian officials in Hariri's killing
Under binding judicial agreements signed by Syria and Lebanon, Habash said, Lebanese judicial authorities have to hand Jumblatt over to Syria.
Jumblatt, who led the anti-Syrian campaign in Lebanon, has scoffed at the summons and was not expected to appear before the Syrian military court.
Habash stressed that the Syrian government, which has not commented on the lawsuit against Jumblatt, had nothing to do with the issue.
However, Habash said he was ready to drop the lawsuit "if he realised that the case would harm Syrian-Lebanese relations".
Relations between Lebanon and Syria sharply deteriorated following a massive truck bombing in Beirut that killed al-Hariri and 20 other people on February 14, 2005.
Al-Hariri's assassination triggered a major change in Lebanese politics. That, coupled with international pressure, led to the final Syrian troop withdrawal from Lebanon in April last year, ending nearly a three-decade domination of its smaller neighbour.
Jumblatt is a member of Lebanon's anti-Syrian parliamentary majority that has accused Syria of responsibility for al-Hariri's assassination, a charge Damascus has repeatedly denied. A UN probe has implicated top Syrian and Lebanese security officials in al-Hariri's killing.