France's Prime Minister Manuel Valls has warned that more major attacks in Europe are a 'certainty' in a worrying message at the Munich Security Conference.

'We have entered - we all feel it - in a new era characterised by the lasting presence of 'hyper-terrorism',' said Valls, whose country was hit by two Islamist attacks last year.

'We must be fully conscious of the threat, and react with a very great force and great lucidity. There will be attacks. Large-scale attacks. It's a certainty. This hyper-terrorism is here to stay,' he said.

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'We have entered - we all feel it - in a new era characterised by the lasting presence of 'hyper-terrorism',' said France's Prime Minister Manuel Valls

Valls was at the three-day security conference in the southern German city, speaking alongside Russian Prime Minister Dmitry Medvedev.

'The force of the ideological fascination is formidable, and if we have changed era it is because this hyper-terrorism is in the heart of our societies,' he said.

ISIS jihadists wrought havoc on the streets of Paris on November 13, killing 130 in a series of attacks on bars, a football stadium and the Bataclan concert hall.

That came after 12 people were killed in a January attack on the Charlie Hebdo satirical news weekly, which had been in the jihadists' sights since publishing cartoons of the Prophet Mohammed in 2006.

ISIS jihadists wrought havoc on the streets of Paris on November 13, killing 130 in a series of attacks on bars, a football stadium and the Bataclan concert hall

Wounded people are evacuated outside the scene of the hostage situation at the Bataclan theatre

One of the terrorists, Bilal Hadfi, blew himself near the Stade de France while France were playing Germany

As the French Prime Minister warned of further violence in Europe, John Kerry urged Russia to change its military targeting as it backs the Syrian regime and warned of the growing migrant crisis.

'We are facing the gravest humanitarian crisis in Europe since World War II,' he said at the Munich Security Conference, which has been dominated by the Syrian conflict which is driving the mass flight.

'The United States understands the near existential nature of this threat to the politics and fabric of life in Europe,' he told the meeting.

'To date, the vast majority of Russia's attacks have been against legitimate opposition groups,' Kerry said. 'To adhere to the agreement it made, we think it is critical that Russia's targeting change.'

Russia has supported the regime of President Bashar al-Assad against rebel forces whom it collectively labels 'terrorists'. The United States has provided some support to the rebels and called for Assad to leave power.

Friday's agreement called for a 'cessation of hostilities' within a week and for greatly increased humanitarian access, but it excludes ISISgroup and al-Qaeda-linked jihadists.

Europe has been deeply split by how to handle the mass influx of people fleeing war-torn Syria, Iraq, Afghanistan and other countries.

Germany took in 1.1 million refugees last year, while Italy and Greece have been overwhelmed as the main arrival points from the Middle East and Africa.

Sweden and Austria have also taken in large numbers, but many EU members, especially in the east, have been deeply reluctant to open their doors.

130 people were murdered in the deadly attacks across the city on Friday 13 November 2015

The attack was later claimed by ISIS, who released a horrific video showing the perpetrators training in Syria

Emergency services tend to a badly injured man who was caught up in the gun attacks last November

'There's a lot of work to do before an effective cessation can commence,' Kerry said.

He stressed this was the crucial moment in a five-year war that has claimed more than 250,000 lives.

'This is the moment. This is a hinge point,' he said. 'Decisions made in the coming days and weeks, and a few months could end the war in Syria - or could define a very difficult set of choices for the future.'

He added: 'The war in Syria has now lasted for almost five years - and shows no signs of burning itself out - which is why we are so focused on a political track.