Parliamentary candidates across the country have clashed over pre-election attacks on Israel.
Labour's Oldham East and Saddleworth MP Phil Woolas has written to Liberal Democrat leader Nick Clegg, questioning his party's views on arms sales to the Jewish state.
Mr Woolas acted after the Lib Dem candidate in the constituency, Elwyn Watkins, wrote to Muslim supporters condemning Israel's "disproportionate use of force" during last year's Gaza conflict and calling for an end to arms sales to Israel.
Mr Woolas wrote: "Is it really your policy that any ban on arms sales should only apply to one Middle East country, namely Israel?"
He noted that Mr Watkins works as an adviser to Sheikh Abdullah Alhamrani, co-owner of one of Saudi Arabia's largest companies.
Mr Watkins said: "Woolas is trying to portray this as me being antisemitic. I'm not antisemitic at all. He has taken something and tried to make it something it's not."
He said his comments were "supported by quite a few million people. It's not an anti-Israel thing. I would not sell rockets to Hamas either. I was following the party line. I would equally condemn Hamas, Hizbollah or whoever targets
civilians."
Mr Clegg's spokesman said: "We called for an EU arms embargo on Israel in the context of Cast Lead and the ongoing blockade of Gaza. While supporting Israel's right to defend itself, we believe that the current approach is not in Israel's own long-term interests."
But Mr Woolas was unavailable to comment on fellow Labour candidate Sonia Nabila Klein's own leaflets in the Ilford North constituency which state she is "fighting for economic sanctions against Israel".
In Hampstead and Kilburn , Tory candidate Chris Philp claimed the Camden Lib Dems had produced leaflets designed to target Jewish voters.
He said the "cheery leaflets" included Hebrew lettering and shots of LibDem candidate Ed Fordham meeting members of the Knesset.
Mr Philp said: "The double standards are truly breathtaking. What the Lib Dems have been doing to whip up hatred against Israel to win votes is totally unacceptable."
Mr Fordham responded: "I'm proud that I have taken a close interest in Jewish and Middle East affairs."