The British parliament is expected to be recalled to debate involvement in airstrikes against the Islamic State, it has been reported, as Prime Minister David Cameron insisted that the fight against the extremist group bidding to create a caliphate in the Middle East was not one anyone could "opt out of."
The BBC reported that the parliament was likely to be convened on Friday to discuss Britain's role in military efforts in Iraq and Syria, though no official confirmation has yet been made. Britain has so far been hesitant to commit resources to the international coalition carrying out airstrikes against the group, with Cameron reportedly frustrated at the lack of support for such a move from lawmakers.
On Tuesday, ahead of Barack Obama's appearance at the United Nations General Assembly to rally support for the fight against the Islamic State, Cameron told NBC News that an international coalition was needed "right across the board" to destroy the "evil organization."
"It (IS) has oil, it has money, it has territory, it has weapons and there's no doubt in my mind it has already undertaken and is planning further plots in Europe and elsewhere," he said in the United States as world leaders gathered for the UN meeting.
"The same applies to the United States of America, so this is a fight you cannot opt out of," he said.
"These people want to kill us."
Iraqi Prime Minister Haider al-Abadi was expected to make a formal request for British participation in airstrikes later on Wednesday.
Cameron suffered a humiliating defeat when he asked the parliament to approve airstrikes in Syria over the Assad regime's use of chemical weapons last summer. Washington ultimately pulled back from intervention on that occasion, but not before US Secretary of State John Kerry hailed a willing France as America's "oldest ally", a remark regarded as a slap in the face for the British government.
The Labour opposition has indicated it might support British involvement in airstrikes in Iraq, but would likely require a United Resolutions before backing intervention in Syria, meaning Cameron might only seek approval for the former.
Ed Miliband, the Labour leader, told the BBC he was "open to the possibility" of supporting aerial attacks against the Islamic State in Iraq.
"How will I judge any proposal? Whether Britain can have an effect, whether we can succeed and whether it is legitimate and lawful. But I am open to the possibility," he said.
"Before I commit British combat troops I want to look at what the proposition is and the nature of that proposition."
He acknowledged, however, that the threat from IS "can't be ignored".
The US has conducted around 200 strikes inside Iraq since August and on Monday began leading an international coalition in air raids in Syria, the first direct foreign involvement in the country since the beginning of its three-year conflict.
On Tuesday Pentagon spokesman Rear Admiral John Kirby said the strikes were believed to have been successful. "We think we have hit what we were aiming at," he told the BBC.
However the Islamic State posed a "serious threat" that would take more than "days or months" to deal with, he said.
"It's going to take a serious effort by all involved. We do believe that we're talking about years here."
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