Anti-IS coalition talks kick off in London

Top officials from 21 countries kicked off talks in London on Thursday on pushing back Islamic State militants in Iraq and Syria and tackling what some say is a growing threat of Europeans returning battle-hardened to carry out attacks at home.

US Secretary of State John Kerry and British Foreign Secretary Philip Hammond co-hosted talks involving 21 of some 60 countries that are working together to tackle the Islamic State group (IS, formerly ISIS) based in Syria and Iraq.

This isn't going to be done in three months or six months. - Phillip Hammond

It will be the first time the US-led coalition has met since this month's attacks in Paris against the satirical magazine Charlie Hebdo and a Jewish supermarket that left 17 people dead.

"Terrorists want to drive us apart, but in fact their actions have had the opposite effect, they're bringing us together," AFP reported Kerry as saying ahead of the talks.

He also called for international action on "the root causes, so that terrorist appeals fall flat and foreign recruits are no longer enticed to go to a place and wreak havoc on it".

A US state department official said foreign fighters would be a "real focus" of the meeting and that an expert working group would be formed on sharing information to stop militants travelling.

The attack on Charlie Hebdo wa sperpetrated by gunmen affiliated with al-Qaeda, while the attacker who shot dead a policewoman and attacked a Jewish supermarket, killing four, claimed he was working on behalf of IS.

European police agency Europol estimates up to 5,000 EU citizens have gone to join the ranks of militants in Syria and Iraq.

Also looming over the meeting is the deadline set by members of the IS group for Tokyo to pay a US$200 million ransom for the release of two Japanese hostages.

Japanese Foreign Minister Fumio Kishida will not be at the London meeting, but held talks with Hammond on Wednesday as Japanese Prime Minister Shinzo Abe admitted it was a "race against time" to free the men.

Hammond, meanwhile, cautioned that the Iraqi army might be months away from mounting a sustained fightback against IS.

He told Reuters news agency that the fight would take years rather than months.

"This isn't going to be done in three months or six months. It's going to take a year, two years to push ISIL (IS) back out of Iraq, but we are doing the things that need to be done in order to turn the tide," Hammond said.

Across town in Downing Street, Prime Minister David Cameron also held talks with Iraqi counterpart Haider al-Abadi.

Abadi defended his country's efforts to repel IS, saying the "Iraqi people have sacrificed their lives" to halt its advance.

"We have reversed, some time ago, the advances of Daesh (IS) and we are very keen to push them back from the whole of Iraq," he told Cameron.

Ministers will also discuss military efforts to support both Iraqi and Kurdish armed forces, how to cut IS financing, and supplying aid for those caught in the crossfire.

The countries confirmed to be attending Thursday's conference are Australia, Bahrain, Belgium, Canada, Denmark, Egypt, France, Germany, Iraq, Italy, Jordan, Kuwait, the Netherlands, Norway, Qatar, Saudi Arabia, Spain, Turkey and the United Arab Emirates.

The coalition last met in Brussels in December.