Mercedes has expanded its technical relationship with Williams to include the supply of gearboxes and hydraulics from 2022 onward.
Mercedes has supplied the British team with engines since 2014, but will expand the deal next year to include "certain transferable components", including the gearbox and related hydraulic components.
Formula One's rules allow for certain components to be bought from a rival team, which are known in the regulations as "non-listed parts".
Williams has historically produced a large number of non-listed parts in-house and taken pride in being an independent team, but under its new owners -- who took charge of the team from the Williams family in September -- it is set mimic the business model of many of its rival teams, which rely on supply deals with bigger teams.