The duo are the only two from the Premier League who are keen. The Blades’ rivals Sheffield Wednesday and Middlesbrough head up the interest from the Championship.
Meanwhile, Charlton Athletic and Sunderland – who meet in the League One playoff final on Sunday – are also keeping tabs.
Those interested in Bonne have been given by a boost by the fact the striker has a £200,000 release clause. Orient have moved quickly to try and get the 23-year-old to sign a new contract and remain in East London.
Who is Bonne?
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A youth product at Colchester United, the forward left his boyhood club in the summer of 2017 to join the newly relegated O’s.
Bonne made an instant impact in the National League, scoring 22 league goals in that first season. However, Orient missed out on promotion back to the EFL.
Bonne remained at Brisbane Road despite reported interest elsewhere and was once again prolific in front of goal in 2018/19. The Zimbabwe international netted 23 times as the East Londoners finished top of the division.
Although born in Ipswich, Bonne has played once for Zimbabwe back in November 2017. The attacker has been named in the Warriors’ 34-man provisional squad for the upcoming African Cup of Nations.
Bonne has applied for a Zimbabwean passport and if successful, will be considered for the tournament. The country are in Group A alongside Egypt, Democratic Republic of Congo and Uganda.
Bonne has previously been compared to Leicester’s Jamie Vardy, which might go some way to explaining why the Foxes are interested.
Meanwhile, the Blades are trying to bolster their squad ahead of a return to the Premier League. They currently only have two senior strikers in David McGoldrick and Billy Sharp.