BAGHDAD — More than 17,000 looted ancient artifacts recovered from the United States and other countries were handed over Tuesday to Iraq’s culture ministry, a restitution described by the government as the largest in the country’s history.

The majority of the artifacts date back 4,000 years to ancient Mesopotamia and were recovered from the U.S. in a recent trip by Prime Minister Mustafa al-Kadhimi. Other pieces were returned from Japan, Netherlands and Italy, Foreign Minister Fuad Hussein said in a news conference with culture minister Hasan Nadhim.

Nadhim said the recovery was the product of months of effort between the government and the Iraqi Embassy in Washington.

“There’s still a lot of work ahead in this matter. There are still thousands of Iraqi artifacts smuggled outside the country,” he said. “The United Nations resolutions are supporting us in the international community and the laws of other countries in which these artifacts are smuggled to are on our side.”

“The smugglers are being trapped day after day by these laws and forced to hand over these artifacts,” he added.

Iraq’s antiquities have been looted throughout decades of war and instability since the 2003 U.S.-led invasion that toppled Saddam Hussein.