The tablet -- whose text is written in cuneiform, the Babylonian alphabet -- bears the insignia of Shalmaneser III, the Assyrian king who ruled the region of Nimrod, in present-day northern Iraq, from 858 to 823 BC.

The circumstances surrounding the tablet's arrival in Italy remain unclear, but the Italian authorities handed it over to Iraqi President Abdul Latif Rashid during a visit to Bologna over the past week.

"I would like to thank the Italian officials for their efforts and cooperation in bringing back this piece," Rashid said during a ceremony Sunday at a Baghdad presidential palace to hand the artefact over to the national museum.

The tablet had arrived in the 1980s in Italy, where it was seized by police, said Laith Majid Hussein, director of Baghdad's council of antiquities and heritage.

Iraqi Culture Minister Ahmed Fakak al-Badrani said the circumstances behind its discovery were unclear.

"Perhaps (it was found) during archaeological excavations or during work on the Mosul dam," Iraq's biggest built in the 1980s, he said.

He underlined the importance of the piece, "whose cuneiform text is complete".

Modern Iraq's territory is the cradle of the Sumerian, Akkadian, Babylonian and Assyrian civilisations, to which humanity owes writing and the first cities.

The country's antiquities have been the target of looting that increased in the chaos following the US-led invasion of 2003.

"We will continue to work to recover all the archaeological pieces of Iraqi history from abroad," said the Iraqi president.

"We want to make the national Iraq Museum one of the best museums in the world, and we will work to do so."

In May, New York prosecutor Alvin Bragg announced the return of two ancient sculptures to Iraq: a limestone Mesopotamian elephant and an alabaster Sumerian bull from the old city of Uruk.

The figurines, stolen during the Gulf War, were smuggled into New York in the late 1990s, according to the prosecutor's office.

The bull was part of the private collection of Shelby White, a billionaire philanthropist and Met trustee.