Russia has accused Britain of "staging" an alleged chemical attack in Syria, as the UN warned the Cold War is back "with a vengeance".

The Kremlin turned the tables on the UK on Friday after Theresa May, Donald Trump and several European leaders accused the Syrian government, supported by Russia and Iran, of carrying out the suspected attack.

At least 70 people are reported to have died and more than 500 injured in the suspected attack last Saturday on Douma, the last rebel-held enclave of eastern Ghouta on the outskirts of Damascus.

Russia's defence ministry claimed the whole attack was faked and it has proof that Britain participated in staging it.

"We have evidence that proves Britain was directly involved in organising this provocation," defence ministry spokesman Igor Konashenkov said.


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Russia ups the ante and blames alleged Syria gas attack on UK

He claimed to know "for sure" that between 3-6 April the White Helmets - the civilian first responders in rebel-held areas - were "under severe pressure specifically from London to produce as quickly as possible this pre-planned provocation".

Mr Konashenkov released statements from medics at Douma's hospital which claim a group of people with video cameras entered the hospital, shouting that its patients were struck with chemical weapons and caused a mass panic.

The medics said none of the patients were hurt by chemicals, he claimed.

Britain's UN envoy, Karen Pierce, said the Russian accusation was a "grotesque, blatant lie" and the UK had no involvement.

"We will not sacrifice the international order we have collectively built to the Russian desire to protect its ally at all costs," she added.

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Image: UN chief Antonio Guterres said the Cold War is back 'with a vengeance'

The accusation came as the US, Britain and France made the case for military action against Syria at an emergency UN Security Council meeting called by Russia on Friday.

The three allies said Syrian President Bashar al Assad's repeated use of chemical wepons posed a threat to the world.

UN Chief Antonio Guterres warned "the Cold War is back - with a vengeance but with a difference" because safeguards that managed the risk of escalation in the past "no longer seem to be present".

He said the Middle East is in such "peril" today that it has become a threat to international peace and security, adding that Syria "represents the most serious threat".

He said that the increasing tensions over Syria could lead to "full-blown military escalation", which he condemned.

Image: Children at a camp for displaced Syrians from Douma

The first of two groups of chemical weapons experts arrived in Syria on Friday to investigate if the weapons were used, he said.

US Ambassador Nikki Haley said no decision had been taken to launch strikes and Washington was taking its time to asses the implications, despite Mr Trump saying on Monday he would make "major decisions" in the next 48 hours.

Citing US estimates that President Assad has used chemical weapons "at least 50 times" in Syria's seven-year civil war, she said: "All nations and all people will be harmed if we allow Assad to normalise the use of chemical weapons.

"But should the United States and our allies decide to act in Syria, it will be in defence of a principle on which we all agree."

France echoed the US stance, saying President Assad's government had reached a "point of no return".

A Downing Street spokesperson said Prime Minister Theresa May and French President Emmanuel Macron had agreed to "keep working closely together on the international response" during a phone call late on Friday.

Image: Russia's UN ambassador Vassily Nebenzia said the US, the UK and France want to oust Assad

Russia dismissed the three allies' arguments, with Russia's UN ambassador Vassily Nebenzia saying they just wanted to "oust the Syrian government and to deter, contain the Russian Federation".

Syria warned it will have "no other choice" but to defend itself if the West launches military action.

"This is not a threat, this is a promise," Syrian ambassador Bashar Jaafari told the UN Security Council.