Washington ? American troops will soon begin helping to train an Afghan army to try to maintain security and guard the borders in that still-unstable nation, Defense Secretary Donald H. Rumsfeld said Monday.

The United States will send no additional troops to do the training, instead using special forces troops already in the country, when they are not engaged in other tasks, Rumsfeld said.

No decision has been made about how large the Afghan army might eventually be, Rumsfeld said, saying that was a decision most likely to be made by the Afghans.

The United States will begin working with other governments to raise money to help pay for the training of the Afghan army and to pay the soldiers themselves, Rumsfeld said. The Bush administration also might consider asking Congress for money to help with the training, the defense secretary said.

So far, British and German members of the international security force in Afghanistan have begun providing basic training for a group of 600 or so Afghans in Kabul.

But thousands of other potential recruits have been waiting, idly and untrained, in tent camps or barracks blocks. So far, most are paid only with a daily plate of onion and potato, although some officers have had meager wages paid by local businessmen. All are so far without uniforms.

“What we’ve decided to do is to try to get it started, and be helpful with one piece,” Rumsfeld said.

The hope is that the first groups of Afghans could then take over much of the training of new classes of recruits, perhaps as early as year’s end, Rumsfeld said.

Gen. Richard B. Myers, chairman of the Joint Chiefs of Staff, said the Afghan army would try to keep security in the country and also help guard the borders.

“One of our missions has been to ensure that Afghanistan is not a safe haven for terrorists,” said Myers. “This assistance we’re going to provide … is directly part of that mission.”

Fighting between regional Afghan warlords has become a problem in some areas since the Taliban were kicked from power, and Rumsfeld has said he believes the key to future stability in the country is the creation of an Afghan army.

The United States has declined to put any military troops into the international security force now in Afghanistan, whose leadership will soon be taken over by Turkey.

The focus of the majority of U.S. troops in the country will be “to track down and try to find … the senior al-Qaida and Taliban in the country,” Rumsfeld said.