Protesters block Iraq's main port of Umm Qasr
Dozens of protesters on Wednesday blocked the entrance of Umm Qasr port in the southern Iraqi city of Basra.
Their action stopped trade and the movement of trucks in and out of the port.
Umm Qasr is the main port for Iraq's grain, vegetable oil and sugar imports.
The protesters vowed to keep blocking the road if the Iraqi government did not meet their demands.
"If they (the government) are not listening to us, we will stay here. They are obliged to listen to us because this port is shared between the political parties and the state, fifty-fifty," a protester told The Associated Press.
"So, let's see. There is everything inside, the trade companies are for the parties, and the ports go for the state. This is clear. If they don't listen to us, we will stay here."
Tens of thousands of Iraqis have been protesting mostly in the capital Baghdad and southern regions since last month.
They are demanding a sweeping change to the political system established after the 2003 US-led invasion, which they blame for widespread corruption, high unemployment and poor public services.
At least 320 people have been killed and thousands wounded since the unrest in the capital and southern provinces began on 1 October.
Amnesty International has slammed the security forces for their alleged use of military-grade tear gas grenades at close range.