England have failed in their attempts to convince Saracens head coach Andy Farrell to join Stuart Lancaster's backroom staff.
Farrell had proved a big hit working with Lancaster and Graham Rowntree during the RBS Six Nations - with England defying the odds to finish as runners-up after registering wins over Scotland, Italy, France and Ireland.
However the secondment was never meant to be permanent - and although Lancaster has been appointed head coach on a full-time basis, Farrell will remain at Saracens.
Farrell told the club's official site: "It has been a special privilege for me to be involved in the Saracens coaching staff for the past two-and-half seasons.
"We have made decent progress during this period but, in truth, as a club, we have barely scratched the surface of our potential.
"The job isn't anywhere near half done, and I have decided I want to help finish the job."
RFU chief executive Ian Ritchie said the search to add to Lancaster's coaching team would now go on.
"Whilst Andy was clearly an important part of the coaching team during the course of the RBS Six Nations, we fully respect his wishes to continue as a coach at Saracens," he said.
"We will continue to work hard with Stuart Lancaster to build a world-class coaching team as we look towards the Rugby World Cup in 2015."
Rowntree will continue as England's forwards coach with New Zealand's attack specialist Wayne Smith now the favourite to join the set-up.
Smith is interested in returning to Test rugby having helped the All Blacks win the World Cup but he is currently unavailable until after England's summer tour to South Africa.