Arsenal have rejected a £20m bid from Leicester for defender Calum Chambers, according to Sky sources.
Sky Sports News understands the Foxes have been pursuing Chambers for some time, with manager Craig Shakespeare keen to strengthen his defensive ranks.
Leicester have already bolstered their defensive options this summer with the addition of England centre-back Harry Maguire from Sky Bet Championship side Hull.
Chambers spent last season on loan at Middlesbrough and made 27 appearances in all competitions as the Teesside club were relegated from the Premier League.
The 22-year-old, capped three times by England, joined Arsenal from Southampton for £16m on a long-term deal in 2014 and appeared 36 times for the first-team during his debut campaign at the club.
But he has since struggled to hold down a regular starting berth and was allowed to leave for Boro last summer.