Alexander Yakovenko has claimed the UK is violating international law by not granting access to the Skripals.

Russia’s ambassador to the UK has stepped up demands to be allowed to see Sergei Skripal and his daughter Yulia, suggesting the pair may be being detained by the British state.

Alexander Yakovenko said the pair were “isolated”, adding: “You can call it kidnap.”

He welcomed the announcement that former spy Mr Skripal had been discharged from hospital after the attack, which the UK authorities have blamed on a military-grade Novichok nerve agent.

Mr Yakovenko has claimed the UK is violating international law by not granting access to the Skripals.

The 1963 Vienna Convention gives consular officials access rights if one of their nationals is in prison, custody or detention.

Setting out Moscow’s interpretation of the case, he said: “We are saying that they are isolated because we don’t have access to them.

“This is our interpretation. You can call it detained, you can call it isolated, you can call it kidnap.

“Unless we see them it is difficult to make a conclusion.”

He acknowledged that the Foreign Office had told him they did not interpret the situation in the same way and added, “I got the impression that we will never see them”.

Russia has denied involvement in the incident in Salisbury which left both Mr Skripal and his daughter seriously ill.

Mr Yakovenko said: “If it was really Novichok and they were poisoned by Novichok, the consequences would be very serious.

“My question was how they survived from Novichok.”

German media deals another crushing blow to UK official version that “only Russia possessed Novichok”: @zeitonline confirms that BND intelligence service had all the information about A234 since 1990s, evidence points to production in several NATO countries pic.twitter.com/cKXBsL7HbF — Russian Embassy, UK (@RussianEmbassy) May 17, 2018

At a press conference at his official residence in London after Mr Skripal was discharged, Mr Yakovenko said “we are happy that he is all right”.

He added: “We are still demanding access to these people. We want to understand how they feel.

“We want them to tell (us) personally what they want. If they don’t want our assistance, that’s fine, but we want to see them physically.”

Mr Yakovenko criticised the Government’s attitude towards Moscow, highlighting Defence Secretary Gavin Williamson’s comment that Russia should “go away and shut up”.

The ambassador said: “We in Russia, we know the price of words. You will never hear from our minister of defence ‘Britain should shut up’. It’s impossible.”

Mr Yakovenko, who was likened to the Iraqi propaganda chief known as Comical Ali during a parliamentary meeting with MPs and peers this week, said he had been given an apology by some lords.

“A few people from the House of Lords came to me yesterday and they apologised for the statements of the MPs,” he said.

“They know the price of words, they know how the ambassador of a big country should be treated.”