Prime Minister Nouri al-Maliki has accused Saudi Arabia and Qatar of supporting fighters in Iraq, Aljazeera reported.
The rare direct attack on the Sunni Gulf powers, comes with Iraq embroiled in its worst prolonged period of bloodshed since 2008, with more than 1,800 people killed already this year, ahead of parliamentary elections due next month.
The bloodletting in the country, which shares a long border with Saudi Arabia, has been driven principally by widespread discontent among the country's Sunni Arab minority and by the civil war in neighbouring Syria.
Maliki, a Shia, has in the past blamed unnamed regional countries and neighbours for destabilising Iraq, the AFP news agency reported.
But in an interview with France 24 broadcast on Saturday, the Iraqi premier said allegations he was marginalising Sunnis were being pushed by sectarians with ties to foreign agendas, with Saudi and Qatari incitement.
"They are attacking Iraq, through Syria, and they announced war on Iraq, as they announced it on Syria, and unfortunately it is on a sectarian and political basis," he said.
"These two countries are primarily responsible for the sectarian and terrorist and security crisis of Iraq."
Saudi Arabia and Qatar have emerged as regional rivals because, while both have provided support to fighters opposed to embattled Syrian President Bashar al-Assad, the two countries have also sparred in recent weeks over Doha's support for the Muslim Brotherhood of deposed Egyptian president Mohamed Morsi.
Saudi Arabia, along with Bahrain and the United Arab Emirates, withdrew its ambassador to Qatar this month.
Baghdad has long complained that support for groups fighting in Syria's civil war finds its way through to Iraq with weapons in particular ending up in the hands of armed groups.
Maliki said in the interview that Riyadh and Doha were providing political, financial and media support to fighters and accused them of buying weapons for the benefit of these organisations.