"The closure of Umm Qasr port harms the country," spokesman Abdul Kareem Khalaf said during a televised press conference on Wednesday.
Protesters have effectively crippled Iraq's main port, which is located in the southern province of Basra, reports Efe news.
"Hundreds of trucks are still parked. This issue is causing massive damage to the nation. Iraq's losses have exceeded $6 billion," Khalaf said.
At least 120 people were injured last week in clashes between protesters and security forces in Umm Qasr, whose crucial role as a hub of Iraq's economy has made it a target for protests and for attempts by various factions to gain leverage.
This second round of protests, like the week-long eruption at the beginning of October, reflects anger over pervasive corruption, economic stagnation and the poor quality of basic services.
Khalaf criticized attempts by protesters to approach oil installations and the offices of foreign companies.
Genuinely peaceful protests don't lead to "the destruction of the economy", the spokesman said, adding that five consecutive days of road-blocking demonstrations have left hundreds of vehicles stranded.
Security forces, Khalaf said, were under strict instructions not to use live ammunition against protesters.
Khalaf's remarks came after the UN Assistance Mission for Iraq said that at least 48 unarmed protesters have been shot dead by security forces in this latest round of protests.
More than a hundred people have died in the second wave of demonstrations, in addition to the 157 who were killed in the unrest that began October 1.
( With inputs from IANS )