An exiled Russian businessman was among anti-Putin protesters at the country's London embassy as voters queued to vote in the presidential election.
Yevgeny Chichvarkin, 43, a mobile phone tycoon who left Russia for the UK in 2008, said he believes the Kremlin is behind the incident in Salisbury, adding that a "change" is needed.
Mr Chichvarkin, who now runs a wine shop in the capital, said the current relationship between the UK and Russia is worse than relations during the Cold War.
The businessman led anti-Putin chants in front of the Russian Embassy in Notting Hill, and was joined by about 30 other protesters.
He said he left Russia due to "serious pressure from Russian authorities", and on the subject of whether he was afraid about being so vocal just a few metres from the embassy, he said: "I feel that I have to."
Asked if he thinks he is being watched, he said: "Of course, a lot of people who work for FSB are around, of course."
But the entrepreneur added: "We need change. We, as the world, we need change."
Mr Chichvarkin said the Kremlin's reaction to the Salisbury incident is "the normal reaction of criminals", and asked if he believes the Kremlin is behind the incident, he said: "Yes. For sure."
Among the protesters standing opposite the embassy was Victoria, 30, who moved to the UK from Moscow.
"I believe that the current elections are fake. I feel like my vote has been taken away from me. And this is the only way I can be honest to myself," she said.
She said she feels Britain should take "more serious" measures against Russia, adding that she believes it is "highly likely" that the Kremlin was behind the Salisbury attack.
Commenting on a tweet posted by the UK Russian Embassy on Sunday - a picture of Poirot with the caption "In absence of evidence, we definitely need Poirot in Salisbury!" - Victoria said that joking about an incident in which people almost lost their lives was "very inappropriate".
She described the state-backed RT TV channel as a "propaganda machine", and said Britain should limit RT's presence.
Also among the protesters was Paulina Konkina, 23, who is originally from Moscow.
She said: "Obviously Russia is my country, it's my home country, so I really want what's best for it, and I don't think Putin is what is best for it."
Ms Konkina said she thinks Russia's reaction to the Salisbury incident has been a form of "bravado".
Meanwhile, a woman queuing to vote, who gave her name as Julia and said she was 56, spoke up for Mr Putin, crediting him with building Russia from scratch.
She said Russia is acting "according to international law", adding: "It is disrespectful to make accusations which are complete lies and slander."
Julia said she does not think the Kremlin was behind the Salisbury incident, adding: "Who wants to do such a thing before the election? It's like to put a gun to your head basically before an election."
Asked about what she thinks of what the British government is saying about Russia, she said: "I think it's disgusting. It's unprofessional. It's not according to international standards."
Another woman in the queue, who gave her name as Vera and said she was 53, said: "I just feel that the accusations are so completely unsubstantiated and ridiculous."
She mentioned Boris Johnson and referred to Gavin Williamson's "shut up and go away" comment, adding: "I just think it's completely unacceptable and it's double standards all over the place.
"And I just feel it's important to be here."
Vera said it would be "really nice" if the British media included the "other point of view", adding: "It's just all one narrative, which I think is Russophobia and it's some part of a big plan and nobody knows what this big plan is."
Valeria Karpova, 47, originally from Moscow, was also at the embassy to vote, and said: "Number one, I'm a Russian citizen and I totally agree with what's happening in Russia at the moment.
"I totally disagree with all lies produced by British press without any evidence, accusing a man personally, and the country altogether - this is appalling, absolutely appalling."
Ms Karpova, who is married to an English man, said they are both "really sorry" to see relations between the two countries deteriorate.