Senior Labour and trade union figures have warned Labour MPs against using the anti-semitism row in which the party finds itself embroiled as part of an effort to oust Jeremy Corbyn.
Diane Abbott, the shadow international development secretary, said the suggestion Labour had a "problem" with anti-semitism was a "smear", while Unite general secretary Len McCluskey said it was being exploited by Mr Corbyn's political enemies.
Speaking on BBC1's Andrew Marr Show, Ms Abbott said: "The Labour party and Labour party members have a lot to be proud of in standing up to racism and anti-semitism long before it was fashionable."
Many say Mr Corbyn has acted too slowly to quell the row, which blew up over alleged anti-semitic comments by his close ally Ken Livingstone and a Facebook post by MP Naz Shah, and there is speculation that MPs are considering launching a challenge to his leadership.
Ms Abbott said she would be "dismayed if some people were hurling around accusations of anti-semitism as part of some intra-Labour Party dispute" and issued a warning that if there were a leadership challenge, Mr Corbyn would still win.
"If people are intent on having a leadership election then we may have one," she said. "But I have to say that if Jeremy is on the ballot then Jeremy wins."
She said that Mr Livingstone's comments - for which he has declined to apologise - were "extremely offensive", but pointed out he had been suspended from the party as a result of them.
Unite general secretary Len McCluskey also dismissed the row, saying Mr Corbyn was the victim of "a cynical attempt to manipulate anti-semitism for political aims".
"The idea that there is an anti-semitic crisis within the Labour Party is absolutely offensive but it is being used in order to challenge Jeremy Corbyn," he told Pienaar's Politics on BBC Radio 5 Live.
Mr Corbyn announced on Friday there would be an independent review into alleged anti-semitism, and pledged to put forward new rules on proper conduct in a bid to end the row.
Labour's London mayoral candidate Sadiq Kahn has indicated he believes the party's mishandling of events could harm his chances at the polls.
He told the Observer that the upper party's leaders needed education and training "as clearly they don't understand what racism is".