Sir Alex Ferguson is reportedly considering a move for Borussia Dortmund striker Robert Lewandowski.

Manchester United are keeping tabs on the Poland international after his agent Maik Barthel reported that contract talks with the Bundesliga champions had broken down.

"I can confirm that the new contract offer of Borussia Dortmund is insufficient," Barthel told Bild.

"I am also able to confirm an interest of Manchester United in the services of Robert Lewandowski."

Lewandowski is currently enjoying his most prolific season to date, scoring 30 goals in 46 matches, including a hat-trick in the 5-3 German Cup final victory over Bayern Munich.