Kit Harington cast as Gilderoy Lockhart in Harry Potter TV series

Kit Harington is joining the highly anticipated Harry Potter TV series as the wizarding world's celebrity-turned-Hogwarts instructor Gilderoy Lockhart.

X-Men star Nicholas Hoult was originally cast in the second series earlier this month but has now left due to scheduling issues, according to HBO.

Best known for playing Jon Snow in Game of Thrones, Harington also appears in BBC and HBO financial drama Industry. The star previously voiced Lockhart in an audio version of Harry Potter.

"I'm a huge Potter fan. I've got to be honest, he's one of my favourite characters," Harington told Collider, external. "So, to be offered to play him is a real dream. I've had a taste of him [in the audiobook] and felt my way around him. He's just a wonderful creation."

Harry Potter and the Philosopher's Stone is due to premiere this Christmas on HBO Max.

Season two will adapt the second book in the series by JK Rowling, The Chamber of Secrets, which chronicles Potter's second year at the magical school.

"Before we begin year two at Hogwarts, there has been a slight change due to schedule: Kit Harington will be stepping into the role of Gilderoy Lockhart," an HBO statement said, external.

The new series adaptation of the best-selling books stars newcomer Dominic McLaughlin as the boy wizard, Alastair Stout as his best friend Ron Weasley and Arabella Stanton as the young witch Hermione Granger.

Oscar-nominated actor Jon Lithgow has been cast as Hogwarts headmaster Albus Dumbledore and Nick Frost will play gamekeeper Rubeus Hagrid.