Moscow: The Russian spy Sergei Skripal gave briefings to European intelligence services in the years before the attempt on his life, which may offer a motive for why Moscow allegedly targeted him with a deadly nerve agent, it was reported on Monday.

According to the Czech magazine Respekt, Skripal visited Prague in 2012 and held discussions with Czech intelligence.

He briefed security officers on Kremlin espionage methods, with the meeting described as “beneficial”.

Members of Czech intelligence subsequently met Skripal in the UK on at least one occasion, the magazine reported.

The claims shed new light on the poisoning of Skripal and his daughter, Yulia, 10 weeks ago in Salisbury. The pair were targeted with novichok, a lethal Soviet-developed nerve agent, in what the UK government says was a clandestine Russian operation.

The Russian government and its embassy in London have furiously denied the claims. They have pointed to the fact that Skripal — a senior officer in the GRU, Russia’s military intelligence outfit — was jailed for spying for the British and later pardoned. He was exchanged in a spy swap in 2010 and settled in the UK. It now appears that Skripal was still active on an informal lecture circuit for former spies.

He gave sensitive briefings to European intelligence agencies after he moved to Britain. It seems that MI6 approved and facilitated these trips. In June 2016 Skripal travelled to Estonia and met a select group of intelligence officers there, the New York Times reported on Monday. It is unclear what they discussed, it said.

Skripal began spying for MI6 in 1995 and worked as a double agent in Spain. CNI, Spain’s foreign intelligence agency, declined to comment on whether he collaborated in recent years with Madrid, saying the question was “a red line we cannot cross”.

Skripal’s case has parallels with that of Alexander Litvinenko, the former FSB officer murdered in 2006 with a radioactive cup of tea. Litvinenko worked for MI6 as a freelance consultant. In the years leading up to his death, he travelled regularly to Spain at the behest of British intelligence.

He advised Spanish spies on the activities of Russian mafia gangs, deeply entrenched in Spain, and their covert links with senior Kremlin figures. Litvinenko agreed to give public evidence. Soon afterwards, Moscow sent two assassins to London to murder him, a public inquiry concluded in 2016.

Detectives are continuing to carry out investigative work on the house where Skripal lived in Salisbury. The nerve agent was smeared on the handle of his front door, the government has said. Yulia Skripal, who was also exposed to the chemical, has been treated and released from hospital.