A deal was agreed with Toyota to supply 1.4-litre common rail diesel engines for the UK-built hatchback.
The D-4D engine was introduced into the Yaris range in March and will be modified for performance and physical fit into the MINI's engine bay.
Trevor Houghton-Berry, general manager for MINI in the UK, said: 'This is a great engine that will complement MINI's renowned chassis and handling.
'It is important that MINI is represented in the growing market for small diesel cars and, as with MINI One, Cooper and Cooper S, we will ensure the diesel MINI will be the most desirable small car in its field.'
Up to 20,000 diesel MINIs will be built at the Oxford plant every year.