Manchester City, Manchester United and Chelsea are monitoring any developments regarding Jamie Vardy's future at Leicester, according to Sky sources.
The England international has been one of the Premier League's form players this season with 15 goals in 20 games.
Vardy's contract at the King Power Stadium - which has two and a half years to run - pays him £40,000 a week and Leicester have yet to offer him a new deal.
United and Chelsea have struggled for goals this season and a January move for Vardy would help boost their faltering attacks.
Vardy turns 29 next week and may not have many more opportunities to join one of the Premier League's biggest clubs. He would also stand to substantially increase his earnings if a transfer does take place.
However, Leicester will be keen to hold on to the man who has been leading their surprise title charge this season in the hopes of securing a top-four finish at least.
Vardy may be able to leverage any potential interest into an improved contract which reflects his status as one of the Premier League's outstanding players this season.