Two Russians resembling men Britain accuses of jetting to England to murder a former spy said on Thursday that they were innocent tourists who had flown to London for fun and visited the city of Salisbury to see its cathedral.

Britain said it was clear the two men, who appeared on Russia's state-funded RT television, were agents of Russia's GRU military intelligence who carried out the attack, and their interview an example of Russia's 'obfuscation and lies'.

The two men, who appeared deeply uncomfortable, identified themselves as Alexander Petrov and Ruslan Boshirov, the names British prosecutors said were used by the poisoners. They said they had fallen victim to a 'fantastical coincidence'.

Britain has charged the two men with attempting to murder former Russian spy Sergei Skripal and his daughter Yulia by spraying a chemical weapon on Skripal's door in March.

The Skripals and a police officer fell seriously ill. A woman in a nearby town later died after her partner brought home a discarded counterfeit Nina Ricci perfume bottle containing the poison.

The two men, both wearing blue jumpers, said they were civilians in the sports nutrition business.

'Our friends had been suggesting for a long time that we visit this wonderful town,' Petrov said of Salisbury.

'There's the famous Salisbury cathedral. It's famous not only in Europe, but in the whole world. It's famous for its 123 metre-spire. It's famous for its clock, one of the first ever created in the world that's still working,' added Boshirov.

Asked about the interview, a British government spokeswoman said: 'The government is clear these men are officers of the Russian military intelligence service – the GRU – who used a devastatingly toxic, illegal chemical weapon on the streets of our country."

"We have repeatedly asked Russia to account for what happened in Salisbury in March. Today – just as we have seen throughout – they have responded with obfuscation and lies.'

Britain and dozens of other countries have kicked out scores of Russian diplomats over the incident, and Moscow has responded tit-for-tat in the biggest East-West wave of expulsions since the Cold War. The affair has worsened Russian relations with the West, already under strain over Ukraine, Syria and other issues.

According to British police, the two men arrived in London on March 2, a Friday, and spent two nights in an east London hotel. They visited Salisbury twice by train on day trips – on the Saturday for reconnaissance and on the Sunday to poison Skripal. They then went straight to the airport and flew home, hours after the Skripals were found unconscious on a bench.

Leisure break

Petrov said he and Boshirov had flown to London for a short leisure break, with Salisbury always intended as a day trip.

'From the very start we planned to go to London and, put bluntly, cut loose and have some fun,' he said in the interview which was pre-recorded on Wednesday and broadcast on Thursday.

'It wasn't a business trip.'

Boshirov said the two men were innocent and had not carried the Novichok nerve agent used in the attack. He laughed off as 'silly' the idea that they would have carried a women's perfume bottle. They may have approached Sergei Skripal's house by chance, but did not know where it was located, they said.

The reason their first visit to Salisbury was so brief was because they had been forced to cut it short due to snow. They then decided to return the next day.

The two men surfaced a day after President Vladimir Putin said Russia had located Petrov and Boshirov, but that there was nothing special or criminal about them. He expressed hope they would come forward and speak publicly.

A European arrest warrant has been issued for the two suspects, but British prosecutors say they will not ask Moscow to extradite Russian citizens because Russia's constitution forbids it.

The Skripal case has been likened by British politicians to the murder of Russian dissident ex-spy Alexander Litvinenko, who was poisoned with a rare radioactive isotope in a London hotel in 2006. Britain charged two Russians with his murder but both remain in Russia, and one later won a seat in parliament.