Schalke interested in Tottenham's Van der Vaart

Schalke chairman Clemens Tonnies has confirmed his club's interest in signing Rafael van der Vaart this summer, although he confessed that it would be a "complicated" deal to negotiate.

Huub Stevens' side ended the season third in the Bundesliga and will qualify for the Champions League group stage next term, two years after reaching the semi-finals of the competition. Tonnies admitted his club will need to strengthen their attack to make up for Raul's departure from the Gelsenkirchen side.

Various names have touted as potential reinforcements in the past weeks, including Eljero Elia, Salomon Kalou and Cacau, but Tottenham's prized attacking midfielder has been the highest-profile player linked.

"Van der Vaart is a very good player, but I have to admit this would be a complicated transfer," Tonnies said in an interview to Sport 1.

The Netherlands international, 29, played under Stevens during his time at Hamburg in 2007-08, and his agent Robert Geerlings confirmed to Kicker that Schalke are heavily interested in his client.

"We think about him but not as intensively as the reports say. If it happens, it will take a long time to materialise," his agent revealed.

Van der Vaart is said to be unhappy with his situation at Spurs as manager Harry Redknapp has forced him to play in several different positions, sometimes from the bench, over the past season. However, he has cooled any talks of a White Hart Lane exit.

"So far I'm content with staying at Tottenham. But in football, you never know what can happen" he said.

Spurs finished fourth in the Premier League but will not feature in the Champions League after their allocation went to Chelsea, who finished sixth but will enter next season's edition as the defending champions.