The new Iraqi government will publish evidence this week linking foreign powers, including Iran and Syria, to the Muslim extremists and loyalists of ousted dictator Saddam Hussein who are behind the insurgency in Iraq.
Foreign Minister Hoshyar Zebari said the interim government had gathered intelligence detailing the support provided to insurgent groups by some neighboring nations.
Although he did not name the countries, senior Iraqi officials indicated that Iran and Syria were the worst offenders.
The accusation that governments in Tehran and Damascus have been aiding the insurgents could create an immediate diplomatic crisis for the Baghdad administration that assumed power last week.
Insurgents have benefited from financial support, logistical assistance and training from neighboring government agencies, Mr. Zebari said. Baghdad also thinks that up to 10,000 foreign spies and undercover agents have infiltrated the country since the war last year.
He even indicated that Baghdad might not oppose attacks by American troops based in Iraq on neighboring states if those states are backing the insurgents.
"Since we started to look at the security situation, we have seen how foreign governments have been helping terrorists," Mr. Zebari said.
"Why they are doing it, we cannot say, but we know where the support is coming from. We have plans to put this before the public within days, and it will have substantial impact."
The accusations fit with remarks last week by Lt. Gen. Ricardo Sanchez, who spoke of an "evolution" in the insurgency during his 14 months as commander of coalition forces.
"We've seen a shift in the power between regime loyalist, the Saddamists, to the terrorists," Gen. Sanchez said in one of his last interviews before leaving Iraq. "They're the biggest threat at the moment."
The general said the terrorist groups, made up of foreign fighters and Islamist extremists, were now focusing almost exclusively on civilians and the reconstruction process.
"They're not attacking my coalition forces. They're after infrastructure, the Iraqi security forces and the interim government, and against the international community to try to split it apart," he said.
Mr. Zebari said it was important for the new government to prove that it was in the "driving seat" in defending Iraqi security, despite the probable diplomatic fallout from naming neighbors as sponsors of terrorism.
Some neighboring countries, he said, had written off the new Iraq, branding the prime minister, Iyad Allawi, and his ministers as American and British stooges.
"Foreign support for terrorists is ongoing, very risky and very dangerous," he said. "But it will backfire on those governments. A stable and peaceful Iraq is a better neighbor for them."
Powerful elements within Iran have been backing radical Shi'ites in Iraq, including supporters of militant cleric Muqtada al-Sadr, who has played a prominent role in the insurgency against the U.S.-led coalition.
Deputy Interior Minister Adnan al-Assadi said hundreds of former Ba'athist officials, who had fled to Syria, were supplying funds and volunteers to the resistance.
For its part, Iran says it has drawn up a list of charges against Saddam for crimes relating to the Iran-Iraq War not included in original charges read against the former dictator, reported the British Broadcasting Corp.