US defence secretary Chuck Hagel is resigning from Barack Obama’s cabinet, sources have revealed.

The head of the extremist Islamic State group has said it will fight to the last man.

Turkey will let US and coalition forces use its bases for attacks against Islamic State (IS) militants in Syria and Iraq, American defence sources have said.

America wants to know how far Turkey is willing to go in helping train and equip moderate opposition fighters trying to topple Syrian president Bashar Assad, including whether it will conduct training on its own land, US defence secretary Chuck Hagel has said.

The US and and five Arab countries have launched air strikes against Islamic State group targets in Syria for the first time, using fighter jets, bombers and Tomahawk cruise missiles fired from ships in the region.

This week will offer the US Congress its best chance to obtain answers about president Barack Obama’s new counter-terror strategy in the Middle East.

Iraq’s parliament has officially named Haider Abadi the country’s new prime minister and approved most of his proposed cabinet.

The United States said it had created a "core coalition" to battle Islamic State militants in Iraq, calling for broad support from allies and partners around the world but ruling out committing ground forces.

While Obama has been criticised for not having a strategy, his desire to build a coalition could prove to be the best policy, writes Jim Gaines.

The Times of London reported yesterday that there are more young British men fighting as jihadists in the Middle East than there are Muslims in the British army.

The head of NATO says it has observed an "alarming" build-up of Russian ground and air forces near the Ukrainian border.

The White House has accused Russia of stepping up its destabilising activity in Ukraine in an “extremely dangerous and provocative” way.

Ukraine said its artillery destroyed part of a Russian armoured column that entered its territory on Thursday night and said its forces came under shellfire from Russia yesterday in what appeared to be a major military escalation between the ex-Soviet states.

US defence secretary Chuck Hagel has said it is far less likely that America will undertake an Iraq rescue mission because fewer refugees are stranded on Sinjar Mountain.

Another 130 US troops have arrived in Iraq on what the Pentagon described as a temporary mission to assess the scope of the humanitarian crisis facing thousands of displaced civilians trapped on Sinjar Mountain.

The grandfather of a seven-year-old boy pictured clutching the severed head of a Syrian soldier has urged the Australian government to bring the child home.

The photograph of a young boy holding the decapitated head of a slain Syrian soldier and published in Australian media underscored the barbarity of Islamist State militants, Australian prime minister Tony Abbott said.

Israel said yesterday it would not bow to international pressure to end air strikes in Gaza that officials there said had killed almost 100 Palestinians, despite an offer by US president Barack Obama to help negotiate a ceasefire with militants.

As the Iraqi government bolstered Baghdad’s defences yesterday, the Islamic militant group that captured two major cities last week posted graphic photos that appeared to show its fighters massacring dozens of Iraqi soldiers.

The United States has ordered an aircraft carrier into the Persian Gulf as it laid out specific ways for Iraq to show it is united in order to gain assistance in its fight against Islamic insurgents.

The Taliban released a video showing Sergeant Bowe Bergdahl being handed over to US forces and bundled into a helicopter in eastern Afghanistan.

Nearly five years after his capture by insurgents, Sgt Bowe Bergdahl’s "safety and health were both in jeopardy" and officials had to act quickly to obtain his release, Defence Secretary Chuck Hagel said yesterday.

The only American soldier held prisoner in Afghanistan has been freed by the Taliban in exchange for the release of five Afghan detainees from the US prison at Guantanamo Bay.

The only American soldier held prisoner in Afghanistan has been freed and is in US custody, according to US officials.

In another devastating blow to Ukraine’s armed forces, rebels shot down a troop helicopter, killing at least 12 soldiers.

The United States has brought cyber-espionage charges against five Chinese military officials accused of hacking into American companies to gain trade secrets.

The United States and other nations in the Group of Seven have agreed to “move swiftly” – as early as Monday – to impose additional economic sanctions on Russia for its actions in Ukraine.

Top diplomats have agreed to take immediate steps toward calming tensions in Ukraine, Russia’s foreign minister says.

One person was killed and 14 injured in a shooting at the US Army's Fort Hood base in Texas, and officials at the base said the shooter is believed to be dead.

As planes spent a third day hunting for two large objects spotted by satellite in the southern Indian Ocean, Australian officials today said they were far from giving up on what remains the strongest lead in the search for Malaysia Airlines Flight 370.

US defence secretary Chuck Hagel has proposed shrinking the army to its smallest size in 74 years, closing military bases and making other military-wide savings as part of a broad reshaping after more than a decade of war.

US Defence Secretary Chuck Hagel is proposing to shrink the Army, closing military bases and making other military-wide savings as part of a broad reshaping of priorities following more than a decade of war.

Ever since the Winter Olympics were awarded to Russia, fears were raised about potential terrorist attacks, which have plagued the country since the collapse of the Soviet Union, writes Dmitri Trenin.

America and Afghanistan have agreed on a security pact that could clear the way for thousands of US troops to train and assist Afghan forces after the Nato combat mission ends in 2014.

As many as 10,000 people are believed to have died in one Philippine city alone when one of the worst storms on record sent giant sea waves, washing away homes, schools and airport buildings.

A possible US national default is looming closer as the partial federal government shutdown continued, rattling markets in the US and overseas.

The White House has signalled that it would be open to a short-term hike in the US debt limit as the United States moved a step closer to its first-ever default while a separate impasse, a partial government shutdown, entered its second week.

It would be “diplomatic malpractice of the worst order” not to test Iran’s willingness to comply with international demands over its nuclear programme, US secretary of state John Kerry said today.

Military action against Syria will deter North Korea from using chemical weapons, a US defence chief says.

Barack Obama is going public to try to convince war-weary Americans that limited strikes against Syria are needed for the United States’ long-term safety.

The US Congress is holding its first public hearing about plans for military intervention in Syria as Barack Obama tries to convince the country of the need to respond to the chemical weapons attack.

Edging toward a retaliatory strike, the Obama administration bluntly accused the Syrian government of Bashar Assad today of launching a chemical weapons attack that killed at least 1,429 people – far more than previous estimates - including more than 400 children.

The US military stands ready to strike Syria at once if president Barack Obama gives the order, the country’s defence secretary Chuck Hagel has said.

Snipers have fired on the UN convoy carrying a team investigating the use of chemical weapons in Syria, but failed to deter them from their mission today.