Troops from Germany are among the forces from a number of allied countries helping the U.S. ground offensive in the war in Afghanistan. But the German government is less than happy that the information is now out in the open.

Officials in Berlin have expressed their irritation at the announcement, made by the Pentagon Sunday, that German forces have joined troops from the United States and five other countries in what has been described as the largest ground offensive so far in the war against al-Qaida and Taleban forces in Afghanistan.

A defense ministry official described the American announcement as unhelpful. He said the government believes the role of the troops should be kept secret to help protect them.

Defense minister Rudolf Scharping has not commented directly on the Pentagon disclosure. He has only confirmed that German forces have been providing medical support to the mission. Defense ministry officials have gone a little further, saying the medical support involved transporting wounded members of Afghanistan's Northern Alliance. But no German official has gone on record as saying German forces are fighting in Afghanistan.

The troops in question are from Germany's elite special forces and are deployed separately from the German contingent pledged to the International Security Assistance Force in Afghanistan - or ISAF. The government announced recently that its soldiers in ISAF will be taking charge of the security brigade protecting the Afghan capital Kabul.

But participating in the fighting is a different matter. As far as is known, it is the first time German troops have been involved in combat outside Europe since the end of the World War II. That makes the U.S. release of information even more sensitive than in countries that are accustomed to sending their soldiers outside the NATO area.