Iran accused U.S. Secretary of State Condoleezza Rice of "Iranophobia" on Sunday for trying to blame Tehran for Iraq's security problems.
Rice said last week she would press Iraq's Arab neighbours at a meeting on Tuesday in Kuwait to do more to support Baghdad's government and shield it from Iran's "nefarious influences".
Iran, as a neighbour of Iraq, will also attend the gathering.
"Regarding Rice's statements, these statements are not something new. American officials follow the policy of Iranophobia," Foreign Ministry spokesman Mohammad Ali Hosseini told reporters in a weekly news conference.
"We see the developments in Iraq today are the outcome of the U.S. administration's illogical policies. The American officials want to externalise the problems they are facing inside Iraq," he said, adding U.S. policies in Iraq had failed.
Washington accuses Tehran of funding, training and arming Iraqi militias, a charge Iran denies. Tehran says the presence of U.S. troops is behind Iraq's problems and wants them out.
Hosseini said Tehran would encourage Arab states to be more active in Iraq where Iran, unlike Arab states, has an embassy.
"We have always encouraged those countries to play a more active role inside Iraq ... and also resume diplomatic relations and open their embassies and support the political process in Iraq," he said.
Arab countries, who are mainly Sunni Muslim, are suspicious of Iran, which like Iraq is majority Shi'ite.
Although Iran and the United States have not had diplomatic ties for almost three decades, officials from both countries held three rounds of talks last year to discuss Iraqi security.
A fourth round of talks has faced several delays, although Baghdad has been encouraging the discussions to continue.
Hosseini said no date had been fixed for the next round of talks.