Obama Anti-IS Coalition Takes Shape as France Joins War

President Barack Obama on Thursday hailed Congress for backing his plan to arm moderate Syrian rebels and France for signing off on air strikes in Iraq, victories for his campaign to destroy the Islamic State group.

U.S. warplanes meanwhile hit an Islamic State group training camp in Iraq in their first strike not directly supporting Iraqi or Kurdish forces as Washington cranked up  pressure on the Sunni extremist group.

Hitting back in the propaganda war, the jihadists posted their latest video of a Western hostage, British journalist John Cantlie. 

Unlike previous grisly postings of two American journalists and a British aid worker being beheaded, Cantlie was only shown speaking to camera in the style of a news report.

In a rare moment of bipartisanship in divided Washington, the Senate voted 78 to 22 to endorse Obama's plan, already passed by the House of Representatives, to arm rebels to take on IS in conjunction with air strikes the president has pledged to carry out inside Syria.

Minutes after the vote, Obama appeared on television, keen to claim a swift victory for his strategy, as polls show Americans support striking IS but are not sure that it will work.

"I want to thank leaders in Congress for the speed and seriousness with which they approached this urgent issue," said Obama.

"These terrorists thought they could frighten us, or intimidate us, or cause us to shrink from the world," he said.

"But today they’re learning the same hard lesson of petty tyrants and terrorists who have gone before."

French President Francois Hollande said that France would join the United States in conducting air strikes against Islamic State -- but only in Iraq.

"As soon as we have identified targets, we will act... within a short timeframe," he vowed.

Obama praised the move by one of America's "oldest and closest allies" which was a boost for his claims to be building a broad international coalition to take on IS.

- First Strike -

The strike on the training camp in northern Iraq killed fighters, as well as destroying buildings and vehicles, U.S. Central Command said. 

A U.S. military officer told AFP that the strike, southeast of Iraq's IS-controlled second city Mosul, was the first of its kind since the U.S. air campaign began on August 8.

About 40 jihadist fighters were on the ground at the time of the strike, the officer said, speaking on condition of anonymity.

A second air raid damaged an IS ammunition depot southeast of Baghdad, Central Command said.

The United States has now carried out 176 air strikes against IS in Iraq.

Even as Congress voted to endorse Obama's plan to train moderate rebels, it was unclear exactly who would benefit.

The rebels battling President Bashar Assad lack a clear command structure and range from secular nationalists to al-Qaida-backed extremists.

But the leader of the Free Syrian Army group, Brigadier General Abdel Ilah al-Bashir, issued a direct appeal to U.S. lawmakers and vowed to crush the Sunni extremists.

"I hereby reaffirm the Free Syrian Army's continued commitment to removing the twin terrorists Bashar Assad and Abu Bakr al-Baghdadi from Syrian soil," he said in a statement, referring to the Syrian president and the leader of IS.

IS holds significant territory in Syria and seized large areas of Iraq in a lightning offensive in June, declaring a cross-border "caliphate" and imposing its brutal interpretation of Islamic law.

- New hostage video -

The Islamic State group has carried out widespread atrocities, including crucifixions and reportedly selling women into slavery, and in recent weeks beheaded two U.S. reporters and a British aid worker in chilling online videos.

The group posted a new video on YouTube showing British journalist Cantlie in an orange jumpsuit like those worn by the hostages in the previous postings, but with no immediate threat to execute him.

In the footage, Cantlie promises to reveal in a series of programs the "truth" about the jihadist group.

Cantlie, who had contributed to British newspapers including The Sunday Times and Sunday Telegraph, as well as to Agence France-Presse, said he was captured after travelling to Syria in November 2012.

It was not clear when the video was shot, but in it Cantlie referred to recent events including the U.S.-led campaign against IS.

In Syria, IS fighters were closing in on the country's third-largest Kurdish town of Ain al-Arab, or Kobane, on the Turkish border, cutting off its Kurdish militia defenders, a monitoring group said.

"IS fighters have seized at least 21 villages around Kobane," Syrian Observatory for Human Rights head Rami Abdel Rahman said. "The IS is using heavy weaponry, its artillery and tanks."

The town is one of three Kurdish majority districts where Kurdish nationalists have proclaimed self-rule and its capture would give the jihadists control of a large swathe of the Turkish border.

The exiled opposition National Coalition warned of "the danger of a massacre" in the area, where Kurdish militia have doggedly resisted the jihadists.

- Global threat? -

Washington estimates that IS has 20,000 to 31,000 fighters, including many foreigners, and there are concerns that returning jihadists could carry out attacks in Western countries.

Australia said it had detained 15 people in connection with a plot to behead random civilians, in the country's largest ever counter-terrorism raids.