"We think it is a problem," Powell said, referring to countries including anti-Iraq war heavyweights France and Germany which are refusing to let their staff assigned to Nato centres in Europe and the United States to be dispatched to Baghdad.
"It is our expectation that when units and individuals are committed to an international staff, they then work in that international staff and become a key part of that international staff," he said on Thursday.
The refusal is hurting the credibility and the cohesion of such the international organisation, he said, speaking after discussing the issue with his Nato counterparts at talks in Brussels.
None the less, Nato said on Thursday it would boost its fledgling military training mission in Baghdad after several European countries responded to US appeals to send trainers to Iraq.
"The number of personnel will go from 60 to 300, including trainers and support staff," Nato Secretary-General Jaap de Hoop Scheffer told reporters after a meeting of foreign ministers from the 26-member alliance.
Scheffer said expansion would go
ahead as soon as possible
He said the expansion would go ahead as soon as possible but gave no precise time-frame for the officer training mission, which is intended to complement the much larger US-led operation to train Iraqi foot soldiers.
Nato also wants to set up a separate military academy on the outskirts of Baghdad with more trainers, but de Hoop Scheffer said that would not be ready before early 2005.
Nato officials said Poland, Hungary, the Netherlands and Norway had volunteered.
Out of the 300 personnel, slightly less than 100 would be trainers with the rest composed of support staff. The training is to take place in the international Green Zone of Baghdad.
The training mission was agreed upon at Nato's Istanbul summit in June after months of wrangling over whether the alliance should have a role in Iraq at all.