Moussa Dembele has scored 20 goals since joining Celtic in the summer

Chelsea are interested in signing Celtic striker Moussa Dembele - but it may cost them £40m to secure the player.

Sky sources understand Celtic are extremely reluctant to sell before Tuesday's transfer deadline and would not consider a bid below £40m.

Dembele's progress has been monitored closely by the Blues going back to his time at Fulham, when he was also of interest to Tottenham and almost signed for Spurs in January 2016.

Moussa Dembele left Fulham at the end of his contract for just £500,000

Celtic paid a nominal £500,000 development fee to sign Dembele after his contract at Craven Cottage expired last summer.

Dembele has scored 20 goals in 38 appearances in all competitions this season.

Chelsea have been discussing bringing in a new striker this month and have been reportedly interested in Swansea forward Fernando Llorente.

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