Efforts by the United States, Britain and France to push for military intervention in Syria have led to acute tensions with Russia and divisions between and within the European powers.

Syria has already descended into a bloody civil war and is now shaping up as an all-out proxy war between the US and Russia. As a result, British Prime Minister David Cameron, who is hosting the G8 summit at Lough Erne, Northern Ireland, has been left floundering in his efforts to secure some form of accommodation between Washington and Moscow.

Attending the two-day summit are US President Barack Obama, Russian President Vladimir Putin, German Chancellor Angela Merkel, French President Francois Hollande, Canadian Premier Stephen Harper, Italian Prime Minister Enrico Letta and Japanese Prime Minister Shinzo Abe.

Formal talks will focus on the global economy, but a “working dinner” last night discussed the situations in Syria and Libya.

Relations between Russia and Britain became overtly hostile Sunday, with Russia making clear that its response to the US arming the Syrian opposition would be to continue arming the regime of Syrian President Bashar al-Assad.

Putin held a press conference with Cameron at Downing Street Sunday. After being asked whether he had “the blood of Syrian children on his hands”—a reference to comments Cameron made at the United Nations—Putin replied, “The blood is on the hands of both parties. There is always a question as to who is to blame.”

“One should hardly back those who kill enemies and eat their organs,” he added, referring to a video of a leader of the Free Syrian Army eating the heart of a government soldier.

Opposing demands that he suspend arms shipments to Syria, he said, “If we speak calmly in cold blood, in a businesslike fashion, let me draw your attention to the fact that Russia supplies arms to the legitimate government of Syria in full compliance with the norms of international law.”

Cameron attempted to downplay the level of disagreement, but a spokesman for Putin told the Independent “that the two sides remained as far apart as ever.”

On Monday, Foreign Ministry spokesman Alexander Lukashevich declared that Russia would not allow the creation of a no-fly zone over Syria. He was responding to reports in the Washington Post that the Obama administration is making preparations for an air exclusion zone, following the Pentagon’s announcement that it will leave behind a squadron of F-16 fighters and a battery of Patriot missiles at the end of joint US-Jordan military drills this week.

“We will not allow this scenario,” said Lukashevich. “Such manoeuvres and arguments are a direct consequence of disrespect for international law. We saw with the example of Libya how such a zone is introduced and how such decisions are implemented. We do not want a repeat of this in respect to the Syria conflict. I think that we will not permit in principle such a scenario.”

Put on the defensive, Cameron has taken to describing the G8 as a “peace conference.” He declared, “There’s clearly a big difference between the Russian position and the position of Britain, France and America and many others.”

Germany was omitted from Cameron’s list of supporters of the US course of action. Although Berlin acceded to the dropping of the European Union arms embargo, Chancellor Merkel declared prior to the summit, “Under no circumstances will we participate in supplying weapons… It is important that a political process gets underway.”

“If we don’t work with the Syrian opposition, then we shouldn’t be surprised when the only parts of the Syrian opposition that are proving effective are the most extreme and the most dangerous,” Cameron told the media. “The Syrian opposition have committed to a democratic, pluralistic Syria that will respect minorities, including Christians.”

Cameron’s problem in taking a hard line with Russia is made worse by the fact that there is no agreement within Britain’s ruling circles on whether the opposition should be armed, let alone on the creation of a no-fly zone or all-out war. Few believe assurances that weapons will go to anyone other than Al Qaeda-linked elements such as the Al Nusra Front.

Conservative London Mayor Boris Johnson, who is shaping up as Cameron’s biggest challenger for leadership of the Tory Party, wrote in a column for the Daily Telegraph, “This is not the moment to send more arms… We can’t use Syria as an arena for geopolitical point-scoring or muscle-flexing, and we won’t get a ceasefire by pressing weapons into the hands of maniacs.”

“This is the moment for a total ceasefire, an end to the madness,” he continued. “It is time for the US, Russia, the EU, Turkey, Iran, Saudi Arabia and all the players to convene an inter-governmental conference to try to halt the carnage.”

According to informed sources, Johnson is speaking for at least 80 MPs and possibly even half the parliamentary party, backed up by five cabinet members. Conservative MP Julian Lewis warned, “I have little doubt that the prime minister would struggle to get [arming the opposition] approved by Parliament because so many of us think it’s not in the British national interest to get involved with this snake pit.”

Nick Clegg, deputy prime minister and leader of the Tories’ coalition partner, the Liberal Democrats, told the BBC’s Andrew Marr, “At this point we’re not providing arms. If we wanted to, we would do it. We clearly don’t think it is the right thing to do now or else we would have decided to do it… We need to work in concert with our allies but we do not need to do the identical thing.”

The British military is also concerned that war against Syria will swing rapidly out of control and result in devastating levels of “blowback.” Former head of the Army, General Sir Richard Dannatt, has said he is “very much in the camp of those who would not wish to be involved and intervene in any shape or form” in Syria.

Major General Julian Thompson, who commanded British forces in the Falklands War in 1982, said, “The thought of getting involved with something else before we finish what we are trying to do in Afghanistan would certainly not be good for morale.”

The Royal Air Force has warned the prime minister it risks losing up to 50 percent of its fighter jets if they are deployed to enforce a no-fly zone because of Syria’s extensive and efficient air defence system.

The pro-Tory Daily Mail notes that “an Internet video” has shown that “a stockpile of surface-to-air missiles” has already “fallen into the hands of jihadists fighting in Syria.” It cites reports that up to 3,000 surface-to-air missiles have gone missing in Libya since the NATO-led war to depose Colonel Muammar Gaddafi.

“More than one million tonnes of weapons belonging to Colonel Gaddafi were looted from arms dumps after the dictator was toppled in October 2011,” it reports. “MI6 agents fear large numbers of weapons—which included 22,000 shoulder-launched missiles capable of bringing down an aircraft—have been smuggled out of Libya to groups linked to Al Qaeda. It is understood MI6 estimates there are now more weapons in Libya than the entire arsenal of the British Army—and much of it is unsecured.”