Everton have reportedly criticised AC Milan for announcing the loan arrival of Gerard Deulofeu before terms have been officially agreed.
The Italian club took to Twitter on Friday evening to declare that the Spanish winger had signed a contract at San Siro for the remainder of the season.
No confirmation was given by Everton, however, and it is claimed by the Liverpool Echo that Toffees chiefs have been left furious by the Rossoneri's conduct.
Milan have since deleted the tweet, with negotiations still understood to be ongoing after the English club rejected an initial approach for the 22-year-old's signature.
Deulofeu made a permanent move to Everton in 2015 for a sum of £4.3m following a successful loan spell.