The frontman for the 1970s rock group Mungo Jerry has denied any links to a venomous "campaign of harassment" against his former manager whose company he is suing for alleged unpaid royalties.

Ray Dorset, lead singer for the band whose classic hit was In the Summertime, is in bitter conflict with his one-time friend and manager, Eliot Cohen, over claims of "under-accounting".

The singer is suing Associated Music International - of which Mr Cohen is a director - which denies the claims.

Mr Dorset's case reached the High Court in a preliminary clash as his barrister, Robert Deacon, asked for permission to add a fresh allegation to the claim.

But the case took a strange twist as Mr Dorset denied harassing his ex-manager by singing in an "antisemitic" video entitled Nail that Snail.

Andrew Sutcliffe, AMI's barrister, said Mr Dorset rejected any links to the video, but added: "That ignores the fact that he was singing, and the DVD which shows Mr Cohen in Nazi uniform was on his official website. His protests of innocence ring very hollow."

But Mr Deacon said: "It has been made clear that a song which Mr Dorset sang has been hijacked and put in a video, unknown to him, and linked to a website he doesn't control. He got that link removed immediately."

Judge Mark Cawson QC said he had seen the video - in which Mr Cohen's head is superimposed on to a Nazi uniform - describing it as "unpleasant and antisemitic so far as it is directed at Mr Cohen". However, he declined to make any findings against Mr Dorset, saying he had "no reason" to doubt his denials.