Toro Ross have confirmed they have reached an agreement with McLaren over the release of technical director James Key.
McLaren announced in June last year that they had signed Key to bolster their technical department, but gave no start date due to an existing contract with Key's current employer, Toro Rosso.
That deal, according to STR team boss Franz Tost is "long-term" – believed to run into 2020 – and initially refused to release Key early.
However a deal has now been struck between the two teams which will see Key start at McLaren on March 25.
"Scuderia Toro Rosso and McLaren Racing confirm they have reached an agreement to settle the position of Mr James Key, who will be released by Scuderia Toro Rosso prior to the end of his existing contract arrangement on March 23rd 2019."
Toro Rosso also confirmed that deputy technical director Jody Egginton would be promoted to fill Key's vacant role.
McLaren chief Zak Brown previously stated that Key would be the "father" of McLaren's 2020 car, with Pat Fry having led the design for their 2019 challenger, the MCL34.