US Secretary of State John Kerry arrived in Paris on Sunday (14.09.2014) to push for a coalition against the terrorist group "Islamic State" (IS), with several Arab nations already offering their support.

With diplomats due to meet in the French capital on Monday, Kerry said a strategy put forward by US President Barack Obama was receiving broad support from US allies.

"This is a strategy coming together as the coalition comes together and the countries declare what they're prepared to do," Kerry said ahead of his arrival in Paris, in an interview with the US television network CBS. "I want it to be absolutely clear out of this discussion we're having that every single aspect of the president's strategy and what is needed to be done in order to accomplish our goal has been offered by one country or multiple countries, and all bases are covered."

Speaking from Paris, one US official said the number of countries signing on was "going up almost every hour," and included countries from Europe and the Middle East right across to Japan, South Korea, and New Zealand.

Pledge to pursue killers

British Prime Minister David Cameron on Sunday pledged to do anything necessary to help defeat "Islamic State" militants after a video emerged depicting the murder of Scottish aid worker David Haines by the IS group.

In a statement delivered at 10 Downing Street on Sunday, Cameron pledged that UK authorities would bring to justice those responsible for beheading Haines, "no matter how long it takes."

Video of the 44-year-old Haines being beheaded by a hooded man with a British accent was posted on the Internet late on Saturday. On Sunday, the British Foreign Office said it had no reason to doubt the authenticity of the footage.

"Step by step we must drive back, dismantle and ultimately destroy ISIL [IS] and what it stands for. We will do so in a calm, deliberate way but with an iron determination," said Cameron. "We will not do so on our own, but by working closely with our allies, not just the United States and in Europe, but with our allies in the region."

IS fighters were "not Muslims, they are monsters," he said, while describing Haines as a "British hero."

'Broad-based strategy' needed

Earlier on Sunday, German Foreign Minister Frank-Walter Steinmeier issued a statement condemning the killing of Haines, and saying it was "an abhorrent act of barbaric violence beyond all limits of human civilization."

Steinmeier also said that the Paris conference on Iraq came at an ideal time for the global community to find a "broad- based and regionally anchored political strategy to confront the threat posed by ISIS [IS]." A statement released by Chancellor Angela Merkel's office said "the unjustifiable act by terrorists must be punished."

Obama has also condemned Haines' beheading and pledged to help bring the perpetrators to justice.

Haines, a former member of the Royal Air Force, had worked for various aid agencies in some of the world's most dangerous places. He had been working for the French-based Agency for Technical Cooperation and Development when he was seized by gunmen in Syria in March 2013.

rc/bk (AFP, AP, Reuters, dpa)