MOSCOW, May 29 (RIA Novosti) - A source in the Russian intelligence community said Tuesday the Litvinenko case is not likely to affect cooperation between Russian and British intelligence services.

The British Sunday Telegraph newspaper recently published an article citing high-ranking British intelligence officers who expressed concerns that the U.K. could lose access to important intelligence data on terrorist groups because of strained relations with Russian security bodies over the investigation into the murder of ex-FSB agent and defector Alexander Litvinenko.

The paper said that British security services have received vital information from Russia on terrorist organizations based in Bosnia, Chechnya and some African countries that helped Britain fight terrorism on its own soil.

But now, U.K. intelligence officials fear that a possible standoff in the Litvinenko murder case could undermine trust in relations with their Russian counterparts.

However, the Russian intelligence source said: "It is unreasonable, to say the least, to put the Litvinenko case and cooperation between the security services of the two countries in the fight against global terrorism on the same scale."

"That cooperation has a deeper meaning and is not affected by short-term political interests," the source said, adding that a lot would depend on actions taken by the U.K.

British prosecutors said last Friday they had filed a request for the extradition of Russian businessman Andrei Lugovoi with the Home Office in connection with the Litvinenko murder case, to be forwarded to Russian authorities.

Lugovoi has denied any role in the murder of Litvinenko, who received U.K. citizenship a few weeks before his fatal radioactive poisoning last November, saying the charges were political.

The British extradition request was made under the European Convention on Extradition and contains a warrant for the arrest of Lugovoi and a detailed summary of the evidence in the case.

Russia's Foreign Ministry confirmed Monday it had received a request from the British authorities to extradite Russian businessman Andrei Lugovoi in connection with Litvinenko's murder.

"The documents have been received and passed on to the General Prosecutor's Office," the ministry said.

Citing the Russian Constitution, Russia's top prosecutor, Yury Chaika, said last week that Lugovoi would not be extradited to Britain but would stand trial in Russia if his complicity were to be substantiated.