Iraqi demonstrators have blocked roads leading to oilfields and the main port in the country's south, according to security officials, while protesters in Baghdad forced the closure of Iraq's central bank.
For the second time since the start of anti-establishment demonstrations last month, protesters on Monday blocked the entrance to the Umm Qasr commodities port near Basra, preventing employees and tankers from entering and bringing operations down by 50 percent, two port sources said.
If the blockage continues, operations will come to a complete halt, the sources told Reuters News Agency. The port was previously blocked from October 29 to November 9 with a brief resumption of operations between November 7-9.
The blockage cost the country more than $6bn during just the first week of closure, a government spokesman said at the time.
Umm Qasr, Iraq's main Gulf port, receives imports of grain, vegetable oils and sugar shipments that feed a country largely dependent on imported food.
Also on Monday, protesters blocked main roads leading to oilfields in the southern Basra province, while in Baghdad staff evacuated the Central Bank as crowds approached the area.
More than 300 people have been killed and 15,000 people wounded since the start of mass unrest in Baghdad and southern Iraq in early October. Security forces have used live ammunition, tear gas and stun grenades against mostly young and unarmed protesters in a bid to put down the popular protests.
Demonstrators are demanding the overthrow of a political class seen as corrupt and beholden to foreign interests. They have turned to civil disobedience tactics such as strikes, disrupting traffic and blocking ports or oil facilities.
The year-old government of Prime Minister Adel Abdul Mahdi has tried to quell the unrest by pledging to reshuffle his cabinet and deliver a package of reforms, but the moves have failed to appease the demonstrators.
Iraq's President Barham Salih has meanwhile promised to hold a snap parliamentary election once a new law is passed, but has not outlined any timeline for the vote.
On Friday, Iraq's top Shia leader, Grand Ayatollah Ali al-Sistani, called for the new election law to restore public confidence in the country's political system.
In a weekly sermon delivered by a representative in the Shia holy city of Karbala, al-Sistani said that a fresh poll would give voters the opportunity to bring "new faces" to power in Iraq.
Al Jazeera and news agencies