Even with the mandate in the recently approved U.S.-Iraq security agreement, there have been suggestions some troops would not leave urban areas. But Gen. Raymond Odierno was the first military leader to acknowledge some forces would remain at local security stations, as training and mentoring teams.

"We believe we should still be inside those after the summer," he said the sprawling U.S. base in Balad, north of Baghdad before welcoming Defense Secretary Robert Gates on a brief visit.

Iraq's prime minister upbraided his top government spokesman for saying some U.S. soldiers might need to remain in the country for many more years. "What was announced about the Iraqi forces needing 10 years in order to be ready is only his personal point of view and it doesn't represent the opinion of the Iraqi government," Prime Minister Nouri al-Maliki's office said in a written statement Saturday.

The spokesman, Ali al-Dabbagh, told reporters in Washington this past week that the Baghdad government would be open to negotiations that would keep troops in Iraq past the agreed upon withdrawal date.

Odierno said he will make recommendations soon on how many troops the U.S. can withdraw from Iraq early next year. There are now about 149,000 U.S. troops in Iraq. That is more than 10,000 higher than before the buildup President George W. Bush ordered in early 2007.

President-elect Barack Obama has pledged to pull combat forces from Iraq in 16 months and the new security agreement calls for a U.S. withdrawal by 2012.

Odierno looked ahead to a series of Iraqi elections, including provincial voting in January, and said, "It's important that we maintain enough presence here that we can help them get through this year of transition."

He added, "We don't want to take a step backward because we've made so much progress here."

Gates' stop in Iraq comes at a critical time. The U.S. is preparing for the troop reduction even as intermittent spikes in violence continue. An important question is whether the Iraqis are ready to take over security and will they be ready when U.S. troops withdraw from urban areas.

Odierno said that overall he believes the Iraqis will be prepared, but that there are a few trouble spots, including Mosul in the north. If the Iraqis believe they need more help in Mosul after June, he said, they can ask for assistance.

He would not say what the prospects are for the Marines to leave the western province of Anbar, where violence has plummeted. Marine leaders have said they want to leave Iraq and head into Afghanistan, where violence has escalated.

The urgent requests from commanders in Afghanistan for more troops has added to the tension to cut troops in Iraq. Military leaders have said repeatedly they cannot send the desired 20,000 or more forces to Afghanistan unless troop levels are cut in Iraq. Gates said that while he is prepared to those troops, he is concerned about having the foreign military force be too large and appear more like occupiers.

Odierno acknowledged that the security improvements in Anbar will allow troop reductions there. He said he will adjust troop levels across Iraq in coming months based on need.

Before stopping in Iraq, Gates attended a meeting in Bahrain of Persian Gulf leaders, where he urged them to help fight the spread of violent extremism by funding and training Afghan security forces and reaching out more aggressively to the Iraq government.

Gates, who will continue as Pentagon chief under Obama, also warned terrorists that "anyone who thought that the upcoming months might present opportunities to 'test' the new administration would be sorely mistaken."

He said Obama and his national security team "will be ready to defend the interests of the United States and our friends and allies from the moment he takes office on Jan. 20."

In his speech, Gates took a more reserved tone on Iran when compared with his sharper criticism in remarks last year that Tehran was a chaotic and destabilizing threat. The defense secretary and others have rebuked Iran for helping bolster militants who cross the border into Iraq. Officials long have believed that Iran has provided money and training to insurgents, and supported the delivery of lethal explosives to Iraq.

On Saturday, Gates pressed Gulf nations to penalize Iran, but added that they can be even more influential "by welcoming the new Iraq into the Arab fold."

Withholding support for the country, he said, increases the risk that Iraq will be overcome by Iranian influence that has already cost many lives.

Asked later about Iran, Gates said Tehran is meddling and attempting to destabilize the region, but said the U.S. is not working to change the government, just Iran's behavior.