Prime Minister Haider al-Abadi sought to reassure Saudi Arabia Sunday that Iraq is not a "gateway for Iran" and will not take part in regional conflicts between the two countries.

"Iraq is not a gateway for Iran," Abadi said in an interview with Iraqiya state TV.

"We do not want to enter in to regional conflicts, and if there are regional conflicts between Saudi Arabia and Iran," Baghdad will not be involved, the premier said.

Iran -- which like Iraq is mostly Shiite Muslim -- and Sunni-majority Saudi Arabia are involved in political and military battles for influence in countries around the Middle East.

Ties between Baghdad and Riyadh have steadily improved since Abadi took office last year after reaching a low ebb under his predecessor Nuri al-Maliki, who accused Saudi Arabia of backing militants in Iraq while it criticised him as sectarian.

Saudi Arabia has named an ambassador to Iraq and announced in January that it would reopen an embassy in the country for the first time in 25 years.

But Baghdad has much closer and longer-standing ties with neighbouring Iran, which is playing a major role in Iraq's battle to regain swathes of territory from the Islamic State (IS) jihadist group.

Tehran has provided weapons to Iraq, and Shiite militias that are among Baghdad's most effective forces have close operational and ideological ties to Iran.

Qassem Suleimani, Tehran's top officer responsible for foreign operations, has along with other Iranians advised Iraqi forces on the ground during multiple operations.

Hadi al-Ameri, the commander of the powerful Badr militia, said earlier this year that Suleimani "is here whenever we need him."

A US-led coalition of dozens of countries is also aiding Iraq in its war against IS, carrying out air strikes against the jihadists and providing training and arms to Iraqi forces.