As a precondition of participating, Israel demanded the UN revoke Resolution 3379 which had determined in 1975 that “Zionism is a form of racism and racial discrimination”.

https://web.archive.org/web/20040513080009/http://www.mfa.gov.il/MFA/Peace Process/Guide to the Peace Process/THE FRUITS OF PEACE

https://en.wikipedia.org/wiki/International_recognition_of_Israel