City were found guilty of having falsely inflated their sponsorship revenues.
The decision is subject to appeal, with City have also been fined €30m (£25m).
A statement from UEFA read: ‘UEFA takes note of the decision of the independent Adjudicatory Chamber of the Club Financial Control Body (CFCB), issued today, which included the following summary of its content and effect to be announced as required by the Procedural Rules governing the CFCB:
‘Following a hearing held on 22 January 2020 the Adjudicatory Chamber of the UEFA Club Financial Control Body (CFCB), chaired by José da Cunha Rodrigues, has today notified Manchester City Football Club of the final decision on the case which was referred by the CFCB Chief Investigator.
‘The Adjudicatory Chamber, having considered all the evidence, has found that Manchester City Football Club committed serious breaches of the UEFA Club Licensing and Financial Fair Play Regulations by overstating its sponsorship revenue in its accounts and in the break-even information submitted to UEFA between 2012 and 2016.
Read more: daily mail