The United States says it is closely watching the trial of an Afghan man who faces the death penalty if he is convicted for converting from Islam to Christianity.

Abdul Rahman, 40, went on trial last week in the Afghan capital, Kabul, accused of converting from Islam to Christianity.  He reportedly converted 16 years ago, but was arrested last month after his relatives, who are observant Muslims, turned him over to authorities.

The case has attracted widespread attention inside Afghanistan and internationally. In Europe, Germany and Italy have called for Abdul Rahman's immediate release saying the trial is a cause for great concern.

But the United States, which led the liberation of Afghanistan from the hard-line Taleban in 2001, has stopped short of calling for his release.  U.S. Undersecretary for Political Affairs Nicholas Burns spoke about the case Tuesday during a joint news briefing with Afghan Foreign Minister Abdullah in Washington.

"We believe in universal freedoms, and freedom of religion is one of them," he said.  "But I should also note, more particularly concerning this case, that the Afghan constitution as we understand it, also provides for freedom of religion."

He said the United States understands the complexity of the case and would respect the sovereignty of the Afghan judicial system. But he added that from an American perspective, people should be free to choose their religion without penalties, especially prison or death.

Undersecretary Burns said he discussed the case with Foreign Minister Abdullah and told him the United States hopes the trial will be held in a transparent way.

The Afghan foreign minister said he only learned of the trial two days ago, but he understands the concerns of the American people, hundreds of whom have sent messages to the Afghan embassy.

"But I hope through our constitutional process there will be a satisfactory result out of that process," he added.

The trial is believed to be the first of its kind in Afghanistan since the Taleban was ousted in 2001.