The interim Libyan leader, Mohammed Magarief, has vowed to disband all illegal militias in the aftermath of the US ambassador's death this month.
All camps and militias not under the authority of the government would be dissolved and no unauthorised checkpoints allowed, he said.
Militias that emerged during the fight to topple Col Muammar Gaddafi last year remain a powerful force.
Residents of Benghazi evicted militants in response to the envoy's death.
Ambassador Christopher Stevens and three others Americans died during an attack on the city's US consulate on 11 September, which coincided with protests over an anti-Islam video produced in the US.
Islamist militants have denied being behind the attack.
Libya has been awash with firearms as well as powerful regional brigades and local town militias since the uprising, the BBC's Rana Jawad reports from the Libyan capital Tripoli.
The government has relied on some brigades to help provide security, and many people will be watching closely to see how the authorities will go about achieving the mammoth task of gaining full military control over the country, she adds.
"[We want to] dissolve all militias and military camps which are not under the control of the state," said Mr Magarief, the parliamentary speaker who acts as head of state until elections next year.
"We call on everyone to stop using violence and carrying weapons in the streets and squares and public places."
One powerful militia in eastern Libya, the Abu Slim Brigade, has already announced it will disband and leave its bases in Derna, a town east of Benghazi.
Another militia, Ansar al-Sharia, which denies attacking the US consulate, is also reported to be leaving Derna.
Ansar al-Sharia was driven out of its headquarters in Benghazi over the weekend in unrest which left at least 11 people dead.
However, the militants left with their weapons.