Iran says it will not hold a fourth round of talks with the U.S. on security in Iraq, as long as U.S. forces continue what it called "open bombings" in Iraq.

Speaking in Tehran today MondayIranian Foreign Ministry spokesman Ali Hosseini said under the current circumstances, any new talks would be meaningless.

U.S. and Iraqi forces have fought fierce battles against Shi'ite militiamen loyal to radical cleric Moqtada al-Sadr in Sadr City for the past month.

In Washington, State Department spokesman Tom Casey said the U.S. is still ready for security talks with Iran, but said they are meaningless as long as Tehran does not change its behavior. The U.S. has repeatedly accused Iran of supporting militias in Iraq, which Tehran denies.

Mohammad Ali Hosseini

In the latest violence in Iraq, the U.S. military says insurgents killed 10 Iraqi soldiers in an attack on a security checkpoint in Diyala province, northeast of Baghdad.

The U.S. military in Iraq also says U.S. forces killed at least nine Shi'ite insurgents during battles in the Sadr City and Mansur districts of Baghdad late Sunday and early today.

Last year, the U.S. ambassador to Iraq, Ryan Crocker, and his Iranian counterpart, Hassan Kazemi Qomi, held three rounds of talks in Baghdad in the first direct diplomatic contacts between Washington and Tehran in nearly 30 years.

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