Sergio Ramos
Manchester United maintain their interest in Ramos but Real still want top dollar for the defender.Getty Images

Manchester United are refusing to let up in their attempts to lure Real Madrid defender Sergio Ramos to Old Trafford and have lodged an offer of €45m (£31.5m, $38.3m) for the defender, AS reports.

But the La Liga giants are not interested in offers that fall below their valuation of the player and are demanding a fee of €90m for the Spain international.

According to a report in Marca on 14 July, Ramos remains determined to leave the Santiago Bernabeu after contract talks with the club broke down at the end of the 2014-15 season.

United are interested in bringing him to Old Trafford and are able to offer the player a salary of €11m, one Real are not prepared to stretch to.

But Real are not interested in accepting an offer below their valuation of the player, who is to captain the club during their pre-season tour of Australia following the departure of Iker Casillas.

And despite his frosty relationship with the player due to the lack of progress in talks, Real president Florentino Perez recently suggested to the press he will not consider selling the centre-half at any price.

"The players who are under contract and leave, it is because they want to," Perez told reporters, Marca report.

"Then there are players who are under contract and leave, and others who the club don't want to leave. Those players will not depart."

United are expected to now focus on strengthening their defence after confirming the arrivals of midfielders Bastian Schweinsteiger and Morgan Schneiderlin. The duo completed their moves to Old Trafford days after the club confirmed the arrival of 25-year-old right-back Matteo Darmian from Torino.

While Real remain unmoved in their stance over Ramos, United are doing likewise with goalkeeper David de Gea. Despite refusing to sign a new contract at Old Trafford, the Premier League giants continue to play hard ball with the Spanish side and insist any move for De Gea must involve Ramos coming in the other direction.