Budget battles are the latest roadblock delaying a decision by Baghdad on how many U.S. troops it might request stay in Iraq, although a top government official predicts the American military will remain as a training force beyond a year-end departure deadline.

Deputy Prime Minister Hussain al-Shahristani said there's no way to estimate how many troops would be asked to stay, or what exactly they will be doing, until parliament passes its $110 billion spending plan for 2012.

Iraq's Cabinet could tentatively sign off on the budget as early as next week, but parliament has until the end of the year to approve it.

"We are on a very tight budget," al-Shahristani said in an Associated Press interview Tuesday. But once the spending plan is settled, "then the Cabinet, and then I expect also the parliament, will approve that training program along with the purchase of the equipment."

Despite the delays, the comments by al-Shahristani, a major figure in Iraq's Shiite political leadership, were one of the most certain signs yet that Baghdad has decided to seek some sort of U.S. presence, likely numbering several thousand. With about three months before the deadline, U.S. leaders are increasingly agitated with Iraq's reluctance to say whether it will ask U.S. troops to stay beyond the Dec. 31 departure date required by a 2008 security agreement between Washington and Baghdad.

Iraqi officials have been torn between their needs for U.S. help in security and public pressure for the Americans to leave _ particularly from Shiite militants who threaten violence if they stay.

There are currently 44,500 U.S. troops in Iraq, due to fall to 40,000 by the end of the month, according to U.S. Joint Chiefs Chairman Adm. Mike Mullen. Starting in October, an estimated 1,000 troops will leave daily.

American officials said Iraq's government has not told them exactly what a continued U.S. military presence would do.

Al-Shahristani, an English-speaking Shiite seen as a possible successor to Prime Minister Nouri al-Maliki, said one task American troops won't be asked to continue is joint patrols with Iraqi forces.

"We are very confident that we have enough trained forces in the country to deal with any terrorist activities or disturbances in Iraq," he said.

But he called it "extremely important" that Americans help in a training program, particularly for Iraq's nascent air and naval forces to protect its airspace and oil terminals in the Persian Gulf.

The mission's size would depend in part on Iraqi defense purchases, including billions of dollars worth of fighter jets and patrol ships Iraq is buying from American manufacturers.

Iraq's Defense Ministry has not told its own government what equipment it needs, said al-Shahristani.

Iraq's budget plan calls for spending $17.1 billion on defense and national security for 2012 _ up from $10.2 billion this year, said government spokesman Ali al-Dabbagh. The rise reflects the need for the new equipment, he said, although promises to give more aid to Iraq's poor, provide nationwide electricity and revitalize cities have stretched funding thin.

Iraq has been looking to buy around $11.5 billion worth of equipment from the U.S. since 2003 _ a quarter of which has not yet been approved. It's not clear how much Iraq has so far spent on the equipment.

When _ or if _ the request comes, there's no guarantee the White House will agree. The U.S. is grappling with its own economic woes, and President Barack Obama is facing re-election after promising in 2009 to end the war in Iraq on schedule.

Mullen told reporters at the Pentagon on Tuesday that it was still too early to say what will emerge from negotiations between Washington and Baghdad.

"It is a hard process to take into consideration, obviously, how the Iraqis see their needs in the future, what they want their relationship with us to be," he said.

The Obama administration is considering 3,000 to 5,000 troops for an Iraqi training mission, according to officials in Washington familiar with the discussions who spoke on condition of anonymity because they were not authorized to release the information. Al-Shahristani said no specific range of numbers for the training mission has been discussed. One Iraqi lawmaker close to al-Maliki, speaking on condition of anonymity because of the sensitivity of the issue, said Baghdad may ask only for about 2,500 forces _ a level that likely would be accepted by his war-weary public.

Another lawmaker, Iskandar Witwit of the Sunni-dominated Iraqiya political coalition _ a rival of al-Maliki's bloc _ said Iraqis could accept a force solely for training or protecting the embassy.

"If it is a battle force, then accepting it would be very hard," said Witwit, deputy head of parliament's defense and security committee.

A training mission would also require the U.S. military to deploy troops to protect the force, the U.S. military says.

Hawkish U.S. politicians and Kurdish officials who have long relied on American support in Iraq argue that a few thousand soldiers will not be enough.

"Such an approach would disregard the recommendations of our military commanders, jeopardize Iraq's tenuous stability and needlessly put at risk all of the hard-won gains the United States has achieved there at enormous cost in blood and treasure," Republican Sens. John McCain and Lindsey Graham and independent Sen. Joe Lieberman said in an opinion article in The Washington Post this week.

The U.S. also insists any deal include legal protections to limit Iraqi courts from prosecuting American forces. Parliament would have to approve immunity, an unpopular move among Iraqis after the 2007 shooting by private U.S. security guards that killed 17 people but could not be prosecuted by Iraqi courts because of an immunity deal.

Al-Shahristani said he could not speculate on whether parliament would approve immunity but maintained his belief that a training mission deal will be reached.

He said all of Iraq's major political groups agree some sort of training mission is needed _ except for the followers of anti-American cleric Muqtada al-Sadr, who has threatened a surge in violence if the U.S. troops remain into 2012.

"We reject even the staying of trainers," said Sadrist lawmaker Mushraq Naji. "Our stance is clear and that all U.S. troops should leave. Negotiations to keep them here run against the will of the Iraqi people."

___

Associated Press Writers Sameer N. Yacoub and Hamid Ahmed contributed to this report.