Image copyright Mercian Regiment Image caption The mascot was promoted at an event marking eight years since the formation of the Mercian Regiment

A sheep which is the mascot of a British Army regiment has been promoted at a ceremony marking its formation.

Private Derby XXX was promoted to the rank of lance corporal at an event in Chester marking eight years of the Mercian Regiment.

He was awarded his honour by the colonel of the regiment, Brigadier Andrew Williams.

The Swaledale ram, who is officially classed as a soldier, received his promotion for "good behaviour".

He is the 30th in a line of mascot rams running back to the Indian Mutiny War in the mid-19th Century.

The first Private Derby was acquired in 1858 by the 95th (Derbyshire) Regiment of Foot and became the mascot of the Mercian Regiment when it formed in 2007.

Lance Corporal Derby XXX joined the regiment in February 2014.

He has his own army number, gets paid to buy his rations and takes his holidays during the mating season on the Chatsworth Estate in Derbyshire.

During his career, Lance Corporal Derby XXX has also helped switch on the Christmas lights in Ashbourne and met Prince William at the unveiling of a memorial commemorating the 1914 Christmas Truce.

Image copyright Mercian Regiment Image caption A ram became the mascot of the Mercian Regiment, in 2007, when the Staffordshire, Worcestershire and Sherwood Foresters and Cheshire regiments merged