Rassie Erasmus said Tuesday his job is done at the Stormers and Western Province, which is why he will move on to a "higher level".
Erasmus was speaking a day after it was confirmed that he quit his position as Senior Professional Coach at WP and the Stormers.
He will leave at the end of January.
"The pieces are in place at Province," said Erasmus in a statement.
"Over the past few seasons we have put the structures in place and they are working well.
"The management team and player base is settled and there are now a fantastic bunch of youngsters pushing the older guys hard. The squad is very close to taking that final step and winning silverware." he added.
He felt that now is the right time to move on.
"My job is largely done here and there is no doubt in my mind that [head coach] Allister [Coetzee], [along with assistants] Matt [Proudfoot], Fleckie [Robbie Fleck] and the rest of the management and players have got what it takes to get there."
He did not confirm, nor deny reports that linked him to a deal that will see him team up with former Bok mentor Nick Mallet at England's national team.
"There are a number of new opportunities that have surfaced at a higher level and I am currently considering my options," he said on his reasons for leaving.
"Each is an exciting and massive new challenge, and that is a big attraction to me at this stage of my career.
"In the interim I have offered to continue to assist at Province whenever required.
"I have enjoyed my time here in the Cape immensely and feel that I have contributed to facilitating building the structures that have taken us to the brink of success. I have no doubt that that success is but a tiny step away now and I leave Province satisfied with the strides made. I am grateful to Province for the opportunity and Newlands, The Stormers, WP and the faithful will always have a special place in my heart."
WP Rugby Managing Director Rob Wagner said Erasmus made a "huge contribution" at WP.
"We are obviously very sorry to see him go, but understand his desire for new challenges," Wagner said.
"Rassie has been very good in keeping us informed of his decision and we have been waiting for the return of our senior players and team management before making the announcement.
"We understand that he is a big loss but we are also confident that the structures, players, coaching and management staff and the plans in place at all levels in the Province, are strong enough to allow us to make that final jump and secure the silverware that we are all working towards."
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