ALLIED ASSISTANCE

But not necessarily the countries usually called allies.

In a relatively modest but welcome bit of relief for American forces, troops from 21 countries including Spain, Poland and four Central American nations will begin taking over duties from U.S. Marines in south-central Iraq this week.

The changeover involving about 10,000 fresh troops comes as President Bush renews efforts to enlist more countries' help in Iraq, hoping that last week's bombing of the U.N. headquarters in Baghdad will motivate heretofore reluctant allies to take part in shoring up security.