The Russian ambassador has denied his country has ever produced the nerve agent novichok used against Sergei and Yulia Skripal in Salisbury.

In a lengthy news conference at the embassy in London Alexander Yakovenko criticised the British Government and claimed the Foreign Office had failed to answer requests for information about the investigation into the attack on the father and daughter last month.

He denied Foreign Secretary Boris Johnson's claim in a tweet that Russia had a "motive" for targeting Mr Skripal.

"It's not true. Absolutely not true. We hear all the stories and the theories about our motivations. We don't buy it. For us, these kinds of statements are unacceptable."

He said novichok was "nothing to do with Russia" and that it was "a creation of some other countries and some scientists".


Mr Yakovenko called for non-NATO countries to be part of the OPCW (Organisation for the Prohibition of Chemical Weapons) investigation and said he wanted to know if British officials were involved.

Mr Yakovenko later dismissed accusations that the Russian Embassy was "trolling" the UK with its Twitter account.

Yesterday, Russia failed to persuade OPCW that they, the chief suspect, should join an investigation of attempted assassinations in Salisbury. Today’s gambit is to rope the UN Security Council into their disinformation campaign. The world will see through this shameless cynicism — Boris Johnson (@BorisJohnson) April 5, 2018

On 18 March the Russian Embassy tweeted: "In absence of evidence, we definitely need Poirot in Salisbury!"

Mr Yakovenko said: "We are not trolling, we are puzzled."

Meanwhile Russia's foreign minister has claimed Britain will not be able to ignore Moscow's "legitimate questions" over the Salisbury attack, ahead of a UN Security Council meeting.

Moscow has demanded an open session of the UN Security Council on Thursday over Britain's claim Moscow was responsible for the poisoning of ex-spy Sergei Skripal and his daughter Yulia.

Ahead of the meeting in New York, Russia's foreign minister Sergei Lavrov called for a "substantial and responsible" investigation into the use of a nerve agent in Salisbury, along with the "presentation of evidence".

He warned: "It will not be possible to ignore the legitimate questions we are asking."

It comes after Russia lost a vote at the global chemical weapons watchdog, where Moscow called for its experts to join the probe into the attack.

Britain said the demand was a sign the Kremlin was "nervous" of what the inquiries will find.

Mr Johnson has tweeted: "Yesterday, Russia failed to persuade OPCW that they, the chief suspect, should join an investigation of attempted assassinations in Salisbury.

"Today's gambit is to rope the UN Security Council into their disinformation campaign. The world will see through this shameless cynicism."

'Production of nerve agent required state actor'

Earlier on Thursday, 60 US diplomats were ordered to leave their embassy in Moscow.

The action is part of Russia's tit-for-tat response to the expulsion of its own diplomats from international capitals in the wake of the Salisbury attack.

Tensions between the UK and Russia have ratcheted up further this week after the head of the Porton Down military research facility told Sky News scientists had not verified Russia as the source of the novichok used on the Skripals.

Russian President Vladimir Putin seized on the comments as he accused the UK of launching an "anti-Russian campaign".

Mr Johnson is facing calls for an inquiry into whether he "misled the public" after he appeared to suggest Porton Down was in "no doubt" the nerve agent in Salisbury originated in Russia.

The Foreign Office later deleted a Twitter post that claimed UK experts had "made clear" the substance was "produced in Russia".

'Porton Down said it was Russia'

Mr Johnson criticised Jeremy Corbyn for "playing Russia's game" after the Labour leader accused him of "exaggeration" over the evidence.

Meanwhile, The Times reported that UK security services have a high degree of confidence that they have pinpointed the location of the Russian laboratory that manufactured the nerve agent used in the attack.

A Whitehall source told the newspaper: "We knew pretty much by the time of the first Cobra (the emergency co-ordination briefing that took place the same week) that it was overwhelmingly likely to come from Russia."