Real Madrid are preparing a £21m ($33m) bid for Arsenal defender Laurent Koscielny amid the uncertainty surrounding the future of Sergio Ramos, according to the Daily Mirror.

Ramos has been heavily linked with a move to Manchester United, with the Red Devils having reportedly made a £35m ($55m) bid for the player. Ramos has only two years left in his current contract and initial reactions suggest that he is not averse to a move to Old Trafford if the right offer presents itself.

President Florentino Perez is reportedly unwilling to hand him the third highest contract at the club behind Cristiano Ronaldo and Gareth Bale, which has led to unrest between the two parties. Should Ramos decide to move, Madrid will have a position vacant in defence, where they want to sign Koscielny, who has recently signed a long-term contract with the Gunners.

The Frenchman, who signed from Lorient in 2010, has established himself as one of the best defenders in Europe in a short span of time, vindicating Arsene Wenger's faith in him and has been a vital member of the squad since his introduction.

It will be a massive blow for Arsenal should he decide to move, with Wenger looking to string in a proper title challenge next season by signing Petr Cech from Chelsea. Koscielny's departure will force him to redraw his back four, which would take time to bed in.

The Gunners ended the season strongly last season but were undone by several injuries and lack of cohesion among new players in the squad at the start, which scuppered their title charge before it started.

Wenger will be hoping that he doesn't have to go through that phase again and have all his players settled for the start of the season, which begins against Chelsea in a fight for the Community Shield on 2 August. Arsenal begin their Premier League campaign at home against West Ham on 7 August.