LONDON - A major row over extremism erupted Saturday night after Labour accused David Cameron of being a far-Right 'propagandist. Britains former secretary of state of Pakistani origin Sadiq Khan made the incendiary remark in response to an outspoken speech by the Prime Minister attacking 'state multiculturalism, calling for a stronger British identity and signalling a crackdown on Muslim groups. Sadiq, the Shadow Justice Secretary, infuriated Downing Street by claiming that Cameron was 'writing propaganda for the English Defence League. The EDL is an anti-Islamist street protest movement that numbers BNP supporters among its members. Labour MPs then weighed in by accusing Cameron of inflammatory timing for making his speech on the day when the EDL was marching in Luton. But Conservatives Chairman Baroness Warsi described Khans remarks as an attempt to 'smear the Prime Minister as a Right-wing extremist. 'This is outrageous and irresponsible, she said. 'David Cameron has made it clear he wants to unite Britain around our common values, and he has done so in measured language. 'It is right that we make it clear: extremism and Islam are not the same thing. Mr Khan ran Ed Milibands leadership campaign. He must apologise and Miliband needs to disown his colleagues baseless accusation. A spokesman for Khan responded: 'The Conservatives are trying to create an artificial row with Sadiq because they realise they have been embarrassed by the timing of Camerons speech. On the day that the EDL marched through Luton and made British Muslims fear to step outside their own homes, it was highly unwise for Cameron to make his speech. Cameron set out the Governments new hardline approach during a major speech on terrorism in Munich. He condemned the 'soft Left who 'lump all Muslims together, compiling a list of grievances and arguing if only governments addressed them. He blamed the 'doctrine of state multiculturalism for 'encouraging different cultures to live separate lives, apart from each other and the mainstream which has contributed to 'the weakening of our collective identity. Cameron, calling for a new 'muscular liberalism, said all public funding would end for groups that give succour to extreme beliefs, such as failing to endorse womens rights. He promised to 'confront the horrors of forced marriage, the practice where young girls are bullied and sometimes taken abroad to marry someone they dont want to. He added: 'When unacceptable views or practices have come from someone who isnt white, weve been too cautious, frankly even fearful, to stand up to them.