The move comes after Spurs allegedly demanded £50 million for the 25-year-old midfielder, significantly more than the £30 million he was thought to be worth on the market.
“Spurs are deadly serious about keeping Modric and it would take insane money for him to leave this transfer window,” a source told the website. “No club in their right mind would pay what Tottenham want, certainly not United without a multi-billionaire backer.”
United will now likely turn their attentions to Internazionale's Sneijder, who has a price tag of around £30 million.
Chelsea are also in the running to sign both players.