The British Asian head of the National Union of Teachers, has warned that teaching British values to students could encourage racism.
Baljeet Ghale and several other experts said any attempt to teach British values would be "fatuous".
Earlier this year, ministers announced that they would include 'core British values' in secondary school citizenship classes to promote better community relations.
Pupils will study aspects of British history and discuss openly their sense of national identity.
Ghale, the NUT's first ethnic minority president, said in her keynote speech: "I have no doubt that for some behind notions of what it means to be British stands the shadow of racism.
"We must never forget that racism is not always overt, but is multifaceted, often subtle and sometimes without malicious intent, she added.
Citizenship education became compulsory in secondary schools five years ago. Topics include politics, voting, the Human Rights Act and the importance of diversity.