Ukraine started a phased pullout of its more than 1,600 troops in March.
Last week, Mr. Yushchenko held talks in Washington with President Bush.
Mr. Bush thanked Ukraine for its contribution in Iraq, and said he understands Mr. Yushchenko's need to fulfill a pledge to have the troops return home.
A number of Ukrainian troops have been injured and 18 have been killed in Iraq. Many Ukrainians oppose the deployment in Iraq.
Some information for this story provided by AP.