Two Russians accused of a nerve agent attack in the UK have admitted they visited the city where the assault took place, but say the purpose of their brief trip was to visit its historic cathedral and not to poison a former double agent who happened to live there, CNN reported.

When the men identified as Alexander Petrov and Ruslan Boshirov visited Salisbury in March, the city was in the snowy grip of the harshest winter to hit England in years.

But they told the Kremlin-backed RT network that the purpose of their 6,000-mile, three-day trip from Moscow was to visit the “wonderful town,” its fine cathedral and other historic sites such as the ancient stone circle at Stonehenge and the prehistoric settlement site of Old Sarum.

Friends had been exhorting them for some time to make the trip, they said. In an interview with RT editor-in-chief Margarita Simonyan, the two men displayed a detailed knowledge of Salisbury cathedral, noting its 123-meter spire and clock, the “first of its kind anywhere in the world.”

They claimed to have had nothing to do with the attack on Sergei Skripal and his daughter Yulia, who were found slumped on a bench as the Russians were on a train back to London. The UK government dismissed the pair's claim that they were merely civilian tourists.

“The lies and blatant fabrications in this interview given to a Russian state-sponsored TV station are an insult to the public's intelligence. More importantly they are deeply offensive to the victims and loved ones of this horrific attack,” Prime Minister Theresa May's spokesman told reporters. “Sadly, it is what we have come to expect. The police have set out very clearly the evidence against these two men. They are wanted men and we have taken all steps to ensure they are apprehended and brought to justice in the UK if they ever again step foot outside Russia.”

British Foreign Secretary Jeremy Hunt ridiculed the Russians’ claims, saying on Twitter: “The last time Russian military claimed to be on holiday was when they invaded Ukraine in 2014. Time to stop the fake TV shows, the world has found Russia out on this.”

Britain is not appealing to Russia for the extradition of the two men as Russian does not extradite its own nationals. However, prosecutors have obtained a European Arrest Warrant and police have asked Interpol to issue arrest warrants too.

British prosecutors said last week they had “sufficient evidence” to charge the two Russian nationals with attempted murder and conspiracy to murder in connection with the attack on March 4.

Prosecutors say the Skripals came into contact with Novichok, a military-grade nerve agent. Russia has repeatedly denied any involvement in the Salisbury attack.