Home Secretary Theresa May has announced plans to outlaw extremist groups and ban them from spreading their message, even if they do not pose a terrorism threat.

But almost immediately the plan came under fire even from some of her fellow Tory MPs.

Even Prime Minister David Cameron compared the move to the widely disparaged broadcasting ban on Sinn Fein leader Gerry Adams during the 1980s and early- 1990s.

Mrs May said that hate preachers could be targeted with "Extremism Disruption Orders (EDOs)" that would allow courts to restrict their movement and activities.

She said that banning orders would help tackle groups not covered by existing terror laws while the new orders would tackle those "who stay just within the law but still spread poisonous hatred".

Ministers want to prevent young people becoming radicalised in the UK and joining Islamic State (IS) terrorists in either Iraq or Syria, before returning home. Mrs May said that everyone living in the UK was free to exercise their right to freedom of conscience, thought and religion but must realise that living in the country comes with responsibilities to respect British values.

She told the Tory party conference: "You don't just get the freedom to live how you choose to live. You have to respect other people's right to do so too and you have to respect British values and institutions - the rule of law, democracy, equality, free speech and respect for minorities.

"These are the values that make our country what it is. These are our values. There is no place for extremism here."

Mr Cameron said the package could involve a broadcasting ban on extremist preachers, similar to that imposed on Mr Adams.

He said: "What we are proposing here is to look at groups who currently are just the right side of not endorsing actual violence but they are preaching extremism."

"There's a very strong argument to say that these extremists are poisoning the minds of young people who are then going on to become violent, and we shouldn't give airtime, we shouldn't give freedom, to these sorts of groups."