The Hornets issued a hands-off warning after the managerless Toffees made an approach on Monday.
Watford immediately rejected the unwanted enquiry for their highly-rated boss insisting publicly yesterday that Silva is staying put at Vicarage Road.
“We will not countenance an approach for our manager, either from Everton or indeed any other club, be it in the Premier League or abroad,” said a club spokesman.
Despite that strong stance, Silva is believed to still be interested in speaking to Everton about succeeding Ronald Koeman at Goodison Park.
Silva only arrived at Vicarage Road in the summer after failing to keep Hull in the Premier League last season.