Both Manchester United and City are keen on signing the star this summer but face competition from some of Europe's leading sides.
Udinese qualified for the Champions League preliminary stages after finishing fourth in Serie A following Sunday's goalless draw against champions AC Milan.
'Once in a generation' player: Alexis Sanchez (right) in action against AC Milan
'For me Sanchez is worth the same as Lionel Messi,' Udinese owner Giampaolo Pozzo said. 'It's difficult to find other players of his level.
'Only two or three players are born like him in a given generation. We have an offer of 35m euros (?30m) which we have turned down. I do not want to name the club, out of respect.
Higher! Udinese have already turned down a ?30m bid for Sanchez
'Sanchez is young and we would like him to stay for another year. Besides, we believe he is worth much more.'
Sanchez, who scored 12 goals in 31 league appearances for Udinese this season, is under contract until June 2014.
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Source: Daily Mail
Source: Daily Mail