Pressure is mounting on the Oxford Union to withdraw speaking invitations to "racists and anti-Semites" following the intervention of nearly a dozen MPs.

Members of the Union will tomorrow vote on whether to go ahead with an event featuring speeches by Holocaust denier David Irving and British National Party leader Nick Griffin.

Mr Irving has been described by a High Court Judge as "an active Holocaust denier... anti-Semitic and racist... who associates with right-wing extremists". Mr Griffin has led the far-right BNP since 1999 and has a conviction for incitement to racial hatred for Holocaust denial.

A public row has prompted union president Luke Tryl to let members vote on the fate of the debate. The event, scheduled for Monday, has been condemned by Oxford East MP Andrew Smith, who said: "These men have a right to eat, but it doesn't mean you have to invite them to dinner. The whole thing is a dangerous publicity stunt by some in the Oxford Union."

Today a Parliamentary motion was tabled supporting Mr Smith's call for the union to retract the invitations.

The motion, signed by nine MPs, accused the Union of seeking to "provide a platform for racists and anti-Semites" and applauded politicians - including Defence Secretary Des Browne - who have withdrawn from speaking engagements at the Union in protest.