Cameron promises decades more war

The PM confirmed that three British nationals had been killed after the Algerian military attacked terrorists holding them hostage at the BP gas field where they worked.

The dead, who have not yet been named, were among hundreds of captives caught in the firefight between soldiers and the Khaled Abu al-Abbas Brigade, one of many Islamic extremist factions in the region.

Mr Cameron said three other British nationals and a British resident were also believed dead.

The Algerian government has been criticised for refusing to negotiate the hostages' release.

But Mr Cameron demurred, saying he recognised "all that the Algerians have done to work with us" - despite previously saying the army had attacked without his knowledge.

He added that the siege was a "stark reminder" of the terrorist threat to Britain.

"This is a global threat and it will require a global response. It will require a response that is about years, even decades, rather than months," he said.

But Stop the War convener Lindsay German said the last decade had already proved the war on terror was doomed to failure.

The Brigade itself had likely bought their weapons from missing stockpiles that Western nations had supplied to rebels in neighbouring Libya two years ago - groups that were otherwise indistinguishable from "terrorists."

"There's still a war going on in Afghanistan with thousands dying every year, there's still massive instability in Iraq. We warned in 2001 that we would only see more and more terrorist groups, and this is exactly what's happened."

Only ending Britain's wars and resource exploitation could genuinely keep the public safe from terrorist attacks, she said.

Recent headlines have described the Brigade as linked to al-Qaida, the Islamic fundamentalist movement popularised by Osama bin Laden.

But commentators say the kidnappers were from a splinter group of al-Qaida in the Maghreb, a loose regional alliance unrelated to Arabic or other networks.

Both the alliance and the Brigade's stated goals are to overthrow the Algerian government, while the Brigade's temporary allies among Tuareg separatists are embroiled in a three-way war between other al-Qaida factions and neigbouring Mali's government for control of their home in the Sahara desert.