Sergei Skripal is no longer in a critical condition following last month's nerve agent attack, Salisbury District Hospital says.

The former Russian double agent is "responding well to treatment" and is "improving rapidly", said Dr Christine Blanshard, medical director at the hospital.

The 66-year-old and his daughter Yulia, 33, have been under the watch of medics since they were attacked with novichok at their home in Salisbury, Wiltshire.

The pair were rushed to hospital after shoppers found them collapsed on a bench at The Maltings shopping centre on 4 March.

Yulia Skripal thanks the people of Salisbury

:: 'Miracle' recovery - How the Skripals survived


On Thursday, Ms Skripal revealed she "woke up over a week ago" and that her "strength is growing daily".

Dr Blanshard said any speculation on when she might be well enough to leave hospital "will be just that - speculation".

In response to news of Mr Skripal's recovery, the Russian Embassy in London tweeted: "Good news!"

Just over a week ago, the ex-spy's best friend Ross Cassidy said they should be allowed to die and that "death would probably be merciful".

Image: Russian Embassy in London responds to Sky News' tweet about Mr Skripal's progress

The latest update on the Skripals' recovery comes as a relative in Moscow revealed she wants to visit her uncle and cousin - but thinks Britain will stop her from coming over.

Speaking to Sky News in Moscow, Viktoria Skripal said she has applied for a visa to visit them, but has been told by staff at the British Embassy in Moscow that it is now up to the UK authorities to decide whether to let her in.

She said she was "pretty sure" she would not be given a visa - despite the efforts of her compatriots.

She reportedly received a phone call from Yulia on Wednesday night who told her "everything is fine" and that "I will be discharged soon", adding that her father was "resting, sleeping".

Viktoria recorded the conversation and it was broadcast on Russian state TV, but its authenticity cannot be verified.

Russia TV airs Skripal niece's 'call with Yulia'

Meanwhile, the war of words continued between Britain and Russia, with Moscow warning the UK it is "playing with fire and will be sorry" during a second UN Security Council showdown over the attempted murders.

Russia's UN envoy Vasily Nebenzya told members that characters in Midsomer Murders knew "hundreds of very clever ways of killing someone", but those who sought to kill the Skripals "supposedly chose an extremely toxic chemical substance, the most risky, dangerous method possible" and "didn't really finish the job".

In another literary nod, he sarcastically likened the British accusations to the queen from Alice In Wonderland who demands the "sentence first - verdict afterward".

British ambassador Karen Pierce hit back, saying she would take no lectures from Moscow and would "stick to the facts" during the terse exchanges.