Manchester United are understood to have made tentative enquiries over the 29-year--old England international but are yet to make an offer, while Arsenal have also been linked.
The latter failed in an attempt to sign Watkins during the January window with an offer, believed to be around £45m, which fell some way short of Villa’s valuation.
Jhon Duran was instead sold to Al-Nassr in a deal which could eventually be worth more than £70m and with Marcus Rashford having returned to United, following his loan spell, Watkins is the only senior forward on the books.
Unai Emery was keen on signing Rashford permanently but Villa’s failure to qualify for the Champions League has made that highly unlikely due to the club’s financial position, coupled with the player’s preference to move abroad.
That has further emphasised the importance of Watkins to Villa’s squad and the difficulty of finding a replacement means it would take a considerable offer for them to think about moving on from a player who has finished top scorer in each of the last five seasons.
United are keen to recruit a striker, with Brentford’s Bryan Mbeumo top of their list. But the Bees refusal to budge on their £63m valuation has forced them to look at alternatives, with Watkins among them.
The Red Devils have also been monitoring Villa goalkeeper Emi Martinez but a move will depend on them first selling current No.1 Andre Onana.
Atletico Madrid, another potential Martinez suitor, would also need to sell their current keeper, Jan Oblak, for the move to work.