The Yugoslav government announced a partial withdrawal of troops and special police units from Kosovo today, but the United States and its NATO allies dismissed the move as insufficient and declared that air attacks on Yugoslavia would continue until Belgrade meets all their conditions to resolve the Kosovo crisis. The announcement, which said the pullback began Sunday, but provided no further details, appeared to be part of a new diplomatic offensive by the Serb-led government to force an end to the allied airstrikes in the aftermath of Friday’s NATO bombing of the Chinese Embassy in Belgrade. Eager to deny Belgrade any diplomatic advantage from the troop pullout declaration, U.S. officials responded that they were unimpressed and reiterated their demands for settling the conflict, including withdrawal of all government security forces from Kosovo and deployment of an international peacekeeping force in the region.