Borussia Dortmund captain Mats Hummels on Wednesday said he was honoured to attract interest from Manchester United but slammed the door shut on any move this year.

The Germany centre-back has been tipped as one of United's top transfer targets but, speaking to media in Singapore, he confirmed earlier reports that he was staying put for now.

"When the big clubs, and Manchester United is one of the biggest clubs in the world, is interested in you, it's an honour and it's a kind of an acceptance of what you play... so it's a good thing," he said during Dortmund's Asian tour.

"There's always been rumours for the last years about almost every one of our players but I decided not to make a move this year and that's the only thing I can say about that," he added.

Hummels, 26, lifted the World Cup in Brazil last year and would be a welcome addition for United as manager Louis van Gaal looks to shore up his defence.

Team-mate Ilkay Gundogan also rebuffed recent United advances and he spoke of his close bond with Japan's Shinji Kagawa, who is back at Dortmund after an unhappy spell at Old Trafford.

"I used to live with Shinji, when I came to Borussia Dortmund, in the same building so for us it was very easy (to get along) because sometimes we drove together to training and also back," said the central midfielder.

"We just started to use one car because it was better for both. After training sessions, we went to dinner or anything and that's how we become really good friends," Gundogan said.

Dortmund have also been to Japan on their tour and they will play in Malaysia on Thursday under new coach Thomas Tuchel, who replaced the influential Jurgen Klopp.

"You see some small differences in training and what he wants us to do with the ball, especially with the way he talks, the way he analyses our games and shows us videos. Of course it's really different," said Hummels.