John Kerry in Paris
US Secretary of State John Kerry (L), next to US ambassador to France Jane D Hartley, delivers a speech at the US embassy in ParisReuters

US Secretary of State John Kerry has arrived in France reaffirming Washington's support following the Paris terror attacks. The top American diplomat will hold talks with French President Francois Hollande on the latest security situation.

Touching down in Paris amid tight security, Kerry said the 13 November attacks reveal how the Islamic State (Isis) was waging a war against "all civilisations". Speaking in fluent French outside the US embassy in France, he said: "I have said many times, as have all of my predecessors, that France is America's closest friend, our first ally. And during our darkest hours, that fact rings truer than ever."

"Don't mistake what these attacks represent. This is not a clash of civilisations, these terrorists have declared war against all civilisation," Kerry said, referring to Hollande's earlier remarks at the extraordinary joint session of parliament.

Kerry's trip, the first by any top American authority since the Paris attacks, was to remain unannounced until the last minute and reporters were asked not to reveal his travel plans because of security concerns. Kerry landed in Paris as he was heading back to the US from Turkey where the world leaders held a summit.

Describing the IS jihadists as "psychopathic monsters", Kerry said: "Tonight we are all Parisians.... Ultimately, we will defeat Daesh [Arabic acronym of Isis] and all who share their despicable ideology." He reiterated that the climate change summit, which kicks off in Paris later in November, would not be cancelled and insisted that President Barack Obama was keen on taking part.

State Department spokesperson John Kirby told reporters: "He (Kerry) will reiterate America's commitment to our strong relationship with France and express our condolences as well as our shared resolve to continue countering violent extremism here and around the world." Kerry has long been pressing for a diplomatic solution in Syria. However, the latest Paris onslaught likely complicated it further.