UK demands Russia deliver polonium killing suspect

Britain's visiting foreign secretary pressed Russia on Monday to turn over the main suspect in the 2006 killing of former Russian security agent Alexander Litvinenko, who died from radioactive polonium poisoning in a London hospital.

Russia has refused to extradite ex-KGB officer-turned-businessman Andrei Lugovoi, saying its constitution forbids extraditing its citizens.

Russian Foreign Minister Sergey Lavrov used the same argument Monday in refusing the request from UK counterpart David Miliband, who said Britain would continue to demand justice in the "horrific murder."

"I suspect that our British counterparts are aware of the fact that a demand to change our constitution is not realistic," Lavrov said, referring to the Russian law forbidding the extradition of Russian citizens.

Lavrov said Russia was willing to prosecute any suspect if Britain provides the evidence. Miliband said Britain has already provided such evidence - which Lavrov denies.

Before his death, Litvinenko recorded a searing message from his hospital bed blaming Russian authorities, including then-President Vladimir Putin, for his killing.

The Litvinenko case pushed British-Russian relations to a post-Cold War low, and ties have been further strained by mutual allegations of spying, Russia's assault on British Council offices and a boardroom dispute at British-Russian venture TNK-BP.

Miliband is the first foreign secretary sent by Britain to Russia in five years, as the British government seeks to improve relations and underline areas where the countries can cooperate.

"There are important areas of common ground alongside well-publicized areas of difference, and we don't compromise on areas of difference by searching for common ground in other areas," Miliband said after the talks Monday with Lavrov.

Miliband's trip to Moscow - falling on the third anniversary of Litvinenko's poisoning - angered Litvinenko's London-based widow, Marina. In a statement last month, she said she was "deeply dismayed" by the timing of the visit.

"The fact remains that a British citizen was murdered in the center of London in a state-sponsored act of nuclear terrorism," she said in the statement. "The apparent softening of Mr. Miliband's position is a great disappointment to me."

Lavrov and Miliband sought to emphasize other areas of shared interest, including collective work to settle the Iranian nuclear standoff and bring peace to the Middle East.

Lavrov said Russia expects Iran to accept a U.N.-backed plan demanding that it ship most of its uranium to Russia for further enrichment and then to France to be turned into fuel rods for use in an Iranian research reactor.

Iran hasn't yet given an answer, insisting instead on simultaneously exchanging its low-enriched uranium for nuclear fuel produced overseas.

"We both want to see a prompt response from the Iranian regime," Miliband said. "Iran can be treated as a normal country for nuclear matters if it behaves like a normal country and respects its responsibilities."

The two foreign secretaries also discussed the 2007 closure of two British Council offices in Russia amid the diplomatic feuding, Miliband told Ekho Moskvy radio. The British Council is the cultural arm of the UK government.

Miliband said that while the talks Monday were "marked by mutual respect, principle engagement on very substantive issues and a genuine search for common ground and common action," Lavrov gave no indication Russia would allow the reopening of the Council offices, which it has accused of back taxes.