The confrontation between Russia and Britain escalated Monday as both sides accused the other of refusing to co-operate in the investigation into the killing of Kremlin critic Alexander Litvinenko.

Deputy prosecutor general Alexander Zvyagintsev speaks at a news conference in Moscow on Monday.
(Sergey Ponomarev/Associated Press)

A high-level Russian prosecutor defended Russia's refusal to extradite former KGB officer Andrei Lugovoi, Britain's prime suspect in the radiation poisoning of Litvinenko in London in November.

"There is no evidence in the materials provided by Britain that there was an objective investigation of the Litvinenko case by Scotland Yard," deputy prosecutor general Alexander Zvyagintsev said at a news conference.

"The Russian side has more grounds to doubt the objectivity of the British justice system," he said.

He said Russian prosecutors are ready to open a case against Lugovoi if there are grounds to do so.

Russia has refused to turn over Lugovoi on the grounds that its constitution forbids the extradition of Russian citizens, but Britain's ambassador to Russia has directly challenged that argument.

In an interview published Monday, Sir Anthony Brenton said Russia could get around the ban if it wanted to co-operate in the case.

"Russia's constitution, like those of other states, is clearly capable of interpretation in the light of circumstances," he said in an interview with the Interfax news agency and Kommersant newspaper.

The ambassador noted specific sections of the constitution that are routinely violated in Russia.

Lugovoi was one of three Russians who met with Litvinenko in a London hotel on Nov. 1, the day he fell ill, but Lugovoi has denied any involvement in his death.

EU ministers to discuss case

The politically charged case was also expected to be discussed at a meeting of European Union foreign ministers in Brussels on Monday.

The extradition dispute may further complicate efforts by the EU and Russia to draw up a new co-operation agreement to replace one expiring in December.

Brenton said Britain was not asking Russia to violate its own constitution, "but to work with us creatively to find a way around this impediment, given the serious and unprecedented nature of this murder. Such co-operation has not been forthcoming."

Russia has offered to try Lugovoi in Moscow if Britain presents sufficient evidence against him. Brenton said this was not an option for British prosecutors, who he stressed were independent of the government.

"They note that the crime was committed against a British citizen and took place in London. The appropriate venue for the trial is therefore London.

"Moreover, both the UN and the EU have stated publicly their concern that the law in Russia is applied selectively," Brenton said. "There would therefore be grounds for a legal challenge against any attempt to accept a trial in Russia."

Britain announced last week that it is expelling four Russian diplomats, restricting visas issued to Russian government officials and reviewing contacts on a range of issues in what it said is a necessary response to Moscow's refusal to co-operate.

Russia countered by saying it will expel four British diplomats, stop issuing visas for British officials and halt counterterrorism co-operation.