British troops in Iraq have begun moving north to take over some operations from US soldiers.
An 850-strong battle group led by the 1st Battalion The Black Watch is moving to a more dangerous part of Iraq.
The US wants to send soldiers to a city in Iraq called Falluja where fighting is very bad. The US military asked for some UK soldiers to fill in for them.
The UK agreed to move the troops to help out, and the prime minister promised they'll be home for Christmas.