Muslim peer Baroness Warsi has hit out at Muslim "hardliners and hotheads" who use Islam to argue against voting and equal rights for women.
Lady Warsi helped win the release of UK teacher Gillian Gibbons
The Conservative shadow minister for community cohesion said it was crucial to distinguish between social demands and genuine religious requirements.
She urged Muslims not to allow such confusion to cut them off from society.
Lady Warsi, speaking at a conference in London, also said Muslims had a special responsibility to defeat extremism.
'Wrong, wrong, wrong'
Addressing the conference on race equality organised by the Guardian newspaper, she said it was possible to be both proud to be Muslim and British and that extremists did not represent the majority of the UK's Muslim community.
"I've got a clear message to the hardliners and hotheads who claim to speak for British Muslims. When you say that voting is un-Islamic, you're wrong.
"When you say that women should not have access to education or employment; that women's equality is un-Islamic; or that women should not adopt leadership positions like politics, you're wrong, wrong, wrong."
Lady Warsi, who lobbied the Sudanese president to secure the release of British schoolteacher Gillian Gibbons after she was jailed for letting her class name a teddy bear Muhammad, called on all Muslims to "engage robustly" with "cultural opinions" about Islamic behaviour where they threatened to divide communities.
She warned that social expectations - "often pretty dubious ones" - should not be mistaken for true religious requirements.
"Confusing the cultural and the religious is wrong because it's divisive - it leads to separation as devout young people think it's their religious duty to cut themselves off from wider society," she said.
"As long as the Muslim community remains in a victim culture, a siege mentality, they allow others to control the debate."
Islam was "unambiguous" in its rejection of forced marriages, she argued, while those behind so-called honour killings should not be permitted "to hide behind any faith".
She went on to say Muslim women should have the choice whether to wear the face veil or not, but acknowledged there would be times when - for reasons of security or health and safety - it would be necessary to remove it.
She called on all members of the Muslim community to help in the fight against terrorism.
"We must accept that we're in all in this together - but Muslims have an added responsibility to defeat extremism, because extremism is claimed in the name of Islam," Baroness Warsi said.
"It's also more personal to us because it's in our community that any backlash is also felt."
The government and society in general also had roles to play in making the Muslim community feel part of the wider community of Britain, she added.