Fylde have agreed to terminate his contract at the Woodlands club.
He asked for a move because of frustration at losing his place in the starting lin-up at the National League One club.
The 33 year old joined Fylde in the 2012/13 season and made 81 appearances, scoring 26 tries in his three and half seasons at the Woodlands.
De La Harpe had previous spells at Moseley, Sale Sharks and West Park (St Helens) and in 2014 was the first player from his country to play for the Barbarians.
Fylde player-coach Paul Arnold said: "We're very sorry that Ryan has asked for his contract to be terminated.
"He's a fine player and has given great service to the club.
"We understand that he wants to be first choice selection at scrum-half but we have other excellent players in that position too.
"We all wish him (and his delightful family) the very best for what ever he goes on to do next.
"He'll always receive a warm welcome at the Woodlands."