West Ham have hardly been having the best time in their new home, but more than a few eyebrows were raised when a steward supposedly representing the club was caught chanting with visiting Manchester United fans at Monday's game.

Footage of United fans singing the "12 days of Cantona" song outside the London Stadium were initially uploaded as part of a longer video by Dutch YouTuber PI Alfa.

A short clip of the video, which showed a man in a bright orange jacket singing along, was quickly edited and posted on social media.

Several West Ham fan accounts picked up on the clip, with several imploring club owners David Gold and David Sullivan to "sort it out".

At one point, Sullivan's son even tweeted to say he had passed the clip on to "higher powers".

Watch the clip below:

Eventually, West Ham cleared up the controversy, explaining that the steward did not represent the club and was in fact a Manchester United employee.

"To clarify, for away games clubs including West Ham United routinely take their own stewards to matches to assist," a club statement read.