DIPLOMATIC tensions between the UK and Russia deepened amid claims that Moscow was blocking investigators from reaching the site of a chemical weapons attack in Syria.

The UK said it was “essential” the Organisation for the Prohibition of Chemical Weapons (OPCW) was granted “unfettered access” to Douma.

Russia strongly denied interfering with the work of inspectors attempting to reach the site of the atrocity which the UK and Western allies have said was perpetrated by the regime of Moscow’s ally Bashar Assad.

And Russian foreign minister Sergey Lavrov said relations between Moscow and the West were worse than at the time of the Cold War.

He said the UK, Nato and European Union had closed the normal channels of communication with Russia which provided safeguards against confrontation.

Asked if he felt he was in a new Cold War, Mr Lavrov told the BBC’s Hardtalk: “I think it is worse, because during the Cold War there were channels of communication and there was no obsession with Russophobia, which looks like genocide by sanctions.”

The latest row between the UK and Russia came as Theresa May prepared to face MPs over her decision to launch air strikes against Syria as Labour questioned the legality of the bombing raid.

The UK’s representative at the OPCW, Peter Wilson, said: “It is imperative that the Syrian Arab Republic and the Russian Federation offer the OPCW fact finding mission team their full co-operation and assistance to carry out their difficult task.”

He dismissed as “ludicrous” a Russian claim the UK had helped stage the attack in Douma, which killed up to 75 people, including a number of children.

He said: “Russia has argued that the attack on Douma was somehow staged, or faked.

“They have even suggested that the UK was behind the attack. That is ludicrous.”

He said Moscow was “spreading conspiracy theories and misinformation” to undermine the integrity of the OPCW’s mission. Relations between Russia and the UK have been plunged into crisis following the nerve agent attack on Sergei and Yulia Skripal.