11.   Eritrea replied, calling for both sides to withdraw troops and submit to mediation.

12.   The ABM treaty allows each side to withdraw from it six months after notifying the other side of its intentions.

13.   The NATO troops subsequently put up a checkpoint in the middle, and the two sides withdrew.

14.   The OAU plan calls for both sides to withdraw troops from disputed areas and allow monitors in while a border commission establishes an international boundary.

15.   The sides withdrew warships from the area after emergency mediation by the United States.

16.   The treaty allows each side to withdraw from it six months after notifying the other side of its intentions.

17.   The warring sides have withdrawn from buffer zones in Bosnia and a cease-fire is holding, the NATO chief said Tuesday.

18.   They subsequently put up a checkpoint in the middle, and the two sides withdrew.

19.   Under rules governing the negotiations, neither side can unilaterally withdraw from talks.

20.   Under that treaty, either side can withdraw by giving six-months notice.