The Conservatives' internal inquiry into MP Aidan Burley said that despite accepting that he left the dinner in protest at one guest raising a Nazi-themed toast, he failed to make it "explicitly clear" that he objected.
"Given the standards expected of a Member of Parliament, he should have done so."
After the incident was made public in 2011, the Conservative MP Aidan Burley wrote a letter to the Jewish Chronicle in which he claimed he "wished I left as soon as I had realised what was happening."
On reflection, I wish I had left as soon as I had realised what was happening. What was happening was wrong and I should have completely dissociated myself from it.
I had a choice, and I made the wrong choice NOT to leave.
I apologise for this error of judgment.
More top news
Tori Lee Castillo, 39, has been arrested on suspicion of child abuse.
Her husband Paul remains in hospital after being seriously injured in the attack -and is it unclear if he knows Elaine has died.
Despite being in the picture, the name of the husband of Luxembourg's gay prime minister was initially left out.