Spokesman James Appathurai says the ministers will decide on granting both nations their membership action plans.

The plans _ seen as the last step before full membership _ are designed to ensure that a candidate nation meets NATO standards in areas such as military reform, civilian control over the armed forces, and transparency in defense budgets.

NATO and EU leaders have expressed concern in recent months over political tensions in Bosnia, where Western troops have maintained the peace since a civil war in the 1990s.

Montenegro, a nation of 630,000 people, gained independence in 2006.