Head coach Martin Haag will leave Nottingham at the end of the current Championship campaign to take up the same role with England's Under-20 side.
Haag, 47, was appointed to succeed Glenn Delaney in July 2012 and led the Green & Whites to second place in the second tier the following year.
The ex-England lock previously played 315 games for Bath and later became forwards coach at the Rec.
"I have thoroughly enjoyed my time at Nottingham," Haag said.
His first task at Twickenham will be to guide the Under-20s through the World Rugby Championship in June.
"Martin is held in high esteem in the rugby world," said the Rugby Football Union's head of international player development Joe Lydon.
"We were impressed with his vision for both player and coach development and his philosophies and values align with those that are in place for the programme."
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Nottingham are currently fifth in the second-tier, nine points behind Yorkshire Carnegie and Bedford above them.
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