Liddle has only played seven first-class matches so far

The 22-year-old left-armer turned down the offer of a new deal from his former club to make the move south.

"It's a privilege to join the best club in county cricket. I can't wait to get down to Hove and to impress," he said.

Sussex manager Mark Robinson described Liddle, who played for Durham at youth level, as an "exciting prospect".

He said: "Chris has the potential to bowl a very lively ball and with his natural left-arm variation should prove an attractive asset to the squad.

"As a person, he should fit well into our family atmosphere."

Liddle will find at least one familiar face at Hove, with Leicestershire's former firector of operations Gus Mackay having recently taken over as Sussex chief executive.