U.S. Sen. Tom Harkin, D-Iowa, says the United States should move ahead with diplomacy to keep Iran from developing military nuclear capabilities.

"I hope we're not headed to war," Harkin said. "I hope that cooler heads can prevail."

He said Iran should reach agreements for the International Atomic Energy Agency to conduct inspections and monitoring so the uranium-enrichment process in that nation does not reach the level of weaponization.

"I remain hopeful that that will happen," Harkin said. "I don't think anyone really wants to go to war with Iran. Well, maybe there are some. I sure hope that that is not in the offing. That would not be good for anyone."

Harkin made the comments Thursday during a conference call with The Daily Times Herald and other media.

President Barack Obama this week affirmed in Israel that the United States will prevent Iran from obtaining nuclear weapons.

"We prefer to resolve this diplomatically and there is still time to do so," Obama said.

The president said, however, that "all options are on the table."

The USA Today newspaper reported Thursday that some experts believe Iran's nuclear program is too far along to prevent it from becoming militarized.

Iran is seeking a diplomatic deal that allows it to keep a nuclear program it says is for medical and research purposes.