Iraq's national security adviser says he believes it is "realistic" to expect, what he describes as, a "considerable" reduction in U.S. and coalition troops in Iraq by the end of next year.

Speaking on CNN's "Late Edition," Iraqi National Security Adviser Mowaffak al-Rubaie said his government is closely examining coalition troop presence in Iraq.

Iraq PM Ibrahim al-Jaafari
"Prime Minister (Ibrahim) Jaafari has proposed to a series of meetings of the ministerial committee on national security, a proposal whereby the multinational forces will pull out from some of the provinces, some of the cities, where the security is okay, and the Iraqi police and new Iraqi army can maintain the security in these regions," Mr. al-Rubaie says.

He added that he hopes this will lead to what he called the "right conditions," and that large numbers of coalition troops in Iraq will no longer be needed.

"I would have a guess of a very good number in terms of thousands, they will leave in the first half of next year, and a considerable number of multi-national forces will probably leave Iraq before the end of next year," Mr. al-Rubaie says.

His remarks follow comments by the top U.S. commander in Iraq, General George Casey, who said he hopes some American forces can be withdrawn from Iraq by the middle of next year, if the democratic process moves forward.

When international troops leave, Iraqi forces will take their place.

Mr. al-Rubaie said he expects the total number of Iraqi security forces to hit 200-thousand by December. But he added that only a fraction of them will be able to function without help.

"We hope by the end of the year, probably more than a third of this Iraq security force (is) going to be able to operate independently," Mr. al-Rubaie says. "And, obviously, you will need the multi-national force to stay over the horizon, just in case they need their help, and they will get the help."

On the same television program, Republican Senator John Kyl indicated he agrees with arguments for reducing American troops in Iraq.

"I do not think we have any way of knowing right now whether that is realistic, but it certainly is the hope," Mr. Kyl says. "That is why the Iraqis are being trained up, in order to be able to take a lot of the fight that our military is engaged in right now. And obviously, that is our hope and our expectation."

Democratic Senator Joseph Lieberman said he thinks the international community should think about sending more troops to Iraq, not cutting numbers.

"I would be surprised if we do not increase the number of American troops, coalition forces, we have on the ground between now and the end of this year, because we have the referendum on the Constitution coming up, we have got the election of the Iraqi Assembly, hopefully in December," Mr. Lieberman says. "Those are times when the terrorists are going to be looking to create havoc.

There are about 139,000 U.S. troops in Iraq.