Bayern Munich midfielder Bastian Schweinsteiger has apologised to Borussia Dortmund fans after a video emerged of him calling them "sons of b*****s".

The World Cup-winning midfielder took to Facebook to issue a grovelling apology after footage showed the 29-year-old singing a derogatory chant about supporters of Bayern's Bundesliga rivals.

He sang "BVB [Dortmund's nickname], sons of b******s" in front of a cheering crowd at what looks like a party.

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But a contrite Schweinsteiger wrote on his Facebook page: "Apology to the BVB! This was certainly not meant that way!"

He also posted a video, in which German daily Bild reports him saying: "Hi, I'm writing from vacation, because I've noticed that a video is distributed of me on the internet. I would like to apologise to all the fans of Borussia Dortmund, managers and players.

"I won't try to play this down - it's obviously a well-known fan song, but I didn't want to insult anyone with the offensive word.

'It's important for me to articulate that now. I get on with all Dortmund players really well, especially Kevin Großkreutz.

'It was an unhappy situation, so sorry again to all Dortmunders, I hope the fans will understand it. All the best, I hope everything's ok again. Your Basti.'

Schweinsteiger was one of Gemmany's key players at the World Cup and was instrumental inDie Mannschaft winning the tournament for the fourth time in the nation's history.

His comment will no doubt inflame the rivalry that already exists between Bayern and Dortmund.

The sides have shared the last five German league titles and Bayern have in recent seasons recruited some of BVB's most coveted stars, including Mario Gotze and Robert Lewandowski.