David Cameron has announced plans to introduce new powers to tackle radicalisation, amid mounting controversy over the proposals.

As the Prime Minister set out his intention to include a new counter-extremism bill in his Queen's Speech later this month, opposition figures and free speech campaigners raised questions about its contents.

New orders will be introduced to ban extremist organisations whose actions fall short of proscription under existing laws and place restrictions on those who seek to radicalise youngsters. Authorities will also be given powers to close premises which harbour extremists.

Mr Cameron revealed the Government plans to fast-track the package as he called on Britain to confront "head-on the poisonous Islamist extremist ideology".

As the Prime Minister briefed ministers at a meeting of the National Security Council, the first indications of the controversy the measures will be met with were emerging.

Liberal Democrat MP Tim Farron accused the Conservatives of fuelling the extremist threat by "playing politics on the basis of division" and creating new tensions.

He said the banning orders - blocked under the previous coalition administration by his party - were "as authoritarian and as Orwellian" as Labour's abandoned plan for national ID cards.

The plans also came under scrutiny from civil liberties groups.

Emma Carr, director of Big Brother Watch, said "serious questions" must be asked about who will be targeted by the measures.

"Before the Government rushes towards introducing legislation, they must clearly outline what type of activities will be deemed as extremist, the process in which activities will be discovered, monitored and subsequently dealt with," she said.

"Clarity on the who, why and how will ensure that the new counter-extremist measure will be targeted and aimed specifically at stopping those who pose a real threat to our way of life."

Sam Bowman, deputy director of libertarian think tank the Adam Smith Institute, said the right to free speech "cannot be conditional on what is being said".

He added: "'Hate preachers' may be bad people but unless they are making direct threats or incitements to violence - which we already have laws against - their ideas must be given the full protection of the law.

"That includes preaching intolerance. Anything less gives the state the power to pick and choose the ideas British citizens can express.

"We should hold these ideas up to scrutiny and challenge them in public debate, not push them into the shadows. With these measures Theresa May has crossed a line - if she pushes ahead, significant liberties will be lost."

Imam and broadcaster Ajmal Masroor said the policy appeared to be "driven by a very extreme right-wing neo-conservative mantra" and would only serve to alienate more people.

However, Tory MEP Sajjad Karim said it was vital to crack down on "targeted operations being carried out by people to try to indoctrinate some of the youngest and brightest people we have got".

He said: "We have not had the tools that we needed before."

Full details of the plans have not been unveiled yet but they are expected to include: :: The introduction of banning orders for extremist organisations who use hate speech in public places, but whose activities fall short of proscription.

:: New Extremism Disruption Orders to restrict people who seek to radicalise young people; :: Powers to close premises where extremists seek to influence others; :: Strengthening the powers of the Charity Commission to root out charities who misappropriate funds towards extremism and terrorism; :: Further immigration restrictions on extremists; :: A strengthened role for Ofcom to take action against channels which broadcast extremist content.

Ahead of today's meeting, Mr Cameron said: "For too long, we have been a passively tolerant society, saying to our citizens: as long as you obey the law, we will leave you alone."

The plans are part of a broad strategy to tackle extremism set out by Home Secretary Mrs May earlier this year.

Mrs May made clear that the new measures would target not only Islamist groups, but also extremists of other kinds, including neo-Nazis.

She told ITV1's Good Morning Britain: "This is a great country to live in, we have a pluralistic society, we are one nation living together. But sadly, there are those who seek to divide us - the extremists of all kinds.

"What we want to do is ensure that those who are trying to promote that hatred and intolerance, we can deal with them."

Ministers responded to the threat posed by Islamic State by introducing a new Counter-terrorism and Security Bill last year. It included new orders that can block alleged British fighters from returning to the UK.

The Government is also expected to revive controversial plans for new laws governing the retention of people's activities on the internet and social media.

In 2013, the Communications Data Bill - labelled a "snoopers' charter" by critics - was shelved after opposition from the deputy prime minister Nick Clegg and the Liberal Democrats.