British Prime Minister David Cameron vowed Monday to make his case for Britain joining air strikes on Syria this week as he unveiled a new defence strategy stressing counter-terrorism and intelligence.

Cameron said he would make a statement in the House of Commons on Thursday as he steps up pressure for MPs to back joining international action against Islamic State jihadists following the November 13 attacks in Paris, which killed 130 people.

His comments came as he presented the Strategic Defence and Security Review (SDSR), which maps Britain's military strategy for the next five years.

"As the murders on the streets of Paris reminded us so starkly, ISIL (another term for Islamic State) is not some remote problem thousands of miles away -- it is a direct threat to our security at home and abroad," Cameron said.

"History teaches us that no government can predict the future... but we can make sure that we have the versatility and the means to respond to new risks and threats to our security as they arise."

Cameron earlier on Monday visited Paris, where he met President Francois Hollande and paid tribute outside the Bataclan concert venue, where 90 people were killed.

"I firmly support the action President Hollande has taken to strike ISIL in Syria," Cameron said after talks in Paris.

"It's my firm conviction that Britain should do so too."

In his speech to parliament, Cameron also announced details of "a significant new contingency plan" in case of attacks in Britain, which would include the rapid deployment of 10,000 military personnel to support the police.

While British forces are taking part in air strikes on IS targets in Iraq, they are not involved in the international effort targeting Syria due to resistance from opposition parties still mindful of previous unpopular interventions in Iraq and Afghanistan.

Labour's anti-war leader Jeremy Corbyn is against any military action but Cameron appears increasingly confident he can get enough support from Labour MPs to pass the vote, particularly after last week's UN Security Council resolution authorising countries to "take all necessary measures" against IS.

- Higher counter-terror spending -

A Times/YouGov opinion poll last week found that 58 percent of people would approve of Britain joining air strikes in Syria, compared to 22 percent against.

Labour's shadow defence minister Maria Eagle also on Monday told BBC radio that "there will be some support from the Labour party for him (Cameron) to do what he wishes" if they approve of his plan.

Reports suggest the government could call a vote on the issue as early as the end of next week. Cameron on Monday only said that the vote could come "in the coming days and weeks".

The SDSR announced Monday has been planned for months but its emphasis on intelligence, counter-terrorism, cyber defence and surveillance spoke volumes about the growing to threat European nations like Britain from groups like IS.

"The SDSR has made interdependence between security at home and security abroad more of a reality," said Michael Clarke, head of the Royal United Services Institute defence think-tank in London.

The review aims to maintain Britain's ability to go war but also "safeguard British society more efficiently from terrorist attack," he added.

The SDSR's 12 billion pounds ($18.2 billion, 17.1 billion euros) of extra investment would create two new 5,000-member rapid reaction strike brigades which could be deployed to conflicts overseas by 2025.

An extra 1,900 security and intelligence staff are being recruited.

Finance minister George Osborne is also expected to announce that counter-terrorism funding is being increased by 30 percent in a budget announcement on Wednesday.

But the budget increase was also accompanied by major cuts, including a 30 percent reduction of the defence ministry's civilian staff and 30 percent of its land being sold.

Osborne also faces a row over claims from police chiefs, who say that cuts to the number of frontline officers who do not fall under the counter-terrorism budget could increase the risk of an attack in Britain.