The United States has reacted cautiously to Iran's offer to help bring the insurgency in Iraq under control.

White House spokesman Tony Snow says officials will have to determine what the offer from Iranian President Mahmoud Ahmadinejad means. The spokesman says the most important thing Iran can do - as he put it - is not finance separatist and terrorist groups trying to undermine democracy in Iraq.

Mr. Ahmadinejad announced the offer Tuesday at a news conference in Tehran with visiting Iraqi Prime Minister Nouri al-Maliki.

In June, the top U.S. commander in Iraq, General George Casey, accused Iran of providing weapons technology and training to Shi'ite extremist groups in Iraq.

In violence Tuesday, more than two dozen people died in attacks in Iraq, including at least six in a car bombing in Baghdad.

Also in the capital, a court is hearing Kurdish witnesses in the trial of former Iraqi leader Saddam Hussein and six co-defendants, accused of ordering the death of tens of thousands of Iraqi Kurds during the 1980s.

And a commander of U.S. forces in Iraq is downplaying reports the security situation in the western part of the country will continue to deteriorate without more troops.

Major General Richard Zilmer said recent media reports highlighting the situation fail to accurately capture the entirety and complexity in Anbar province, the center of the Sunni insurgency.

Some information for this report was provided by AFP, AP and Reuters.