Watch part two

Iraq enters a new phase in its history on June 30, when US troops pull out of Iraqi cities as part of last year's US-Iraqi Status of Forces Agreement.

Only a handful of US military advisers will remain behind to provide support to their Iraqi counterparts, while most of the 133,000 US troops move to bases inside the country. 

The Iraqi government has proclaimed a national holiday to celebrate the occasion. 

But many – both inside and outside Iraq - worry that overall security will weaken under Iraqi control.