The session comes two days after a U.S. drone strike on a convoy at Baghdad airport which killed Iranian military commander Qassem Soleimani and Iraqi militia leader Abu Mahdi al-Muhandis.
"There is no need for the presence of American forces after defeating Daesh (Islamic State)," said Ammar al-Shibli, a Shi'ite lawmaker and member of the parliamentary legal committee.
"We have our own armed forces which are capable of protecting the country," he said.
Despite decades of enmity between Iran and the United States, Iran-backed militia and U.S. troops fought side by side during Iraq's 2014-2017 war against Islamic State militants.
Around 5,000 U.S. troops remain in Iraq, most of them in an advisory capacity.
The militia were incorporated into government forces under the umbrella of the Popular Mobilisation Forces which Muhandis led.
Many Iraqis, including opponents of Soleimani, have expressed anger at Washington for killing the two men on Iraqi soil and possibly dragging their country into another conflict.
Since the killings, rival Shi'ite political leaders have called for U.S. troops to be expelled from Iraq in an unusual show of unity among factions that have squabbled for months.
Hadi al-Amiri, the top candidate to succeed Muhandis, repeated his call for U.S. troops to leave Iraq on Saturday during an elaborate funeral procession for those killed in the attack.
A vote to expel U.S. troops would need parliament to pass a law obliging the Iraqi government to ask U.S. troops to leave.Prime Minister Adel Abdul Mahdi, who is now caretaker prime minister after resigning in November under pressure from street protests, on Friday called for parliament to convene an extraordinary session to take legislative steps to protect Iraq's sovereignty.