Lugovoy

LONDON, (Reuters):

British prosecutors accused an ex-KGB agent yesterday of poisoning Kremlin critic Alexander Litvinenko with radioactive polo-nium and demanded his extradition, setting London and Moscow on a diplomatic collision course.

The Crown Prosecution Service said it wanted to bring suspect Andrei Lugovoy before a British court and charge him with the "extraordinarily grave crime" of murdering exiled Russian Litvinenko in London last November.

Britain's Foreign Office summoned the Russian ambassador and told him in strong terms it expected "full cooperation" over Lugovoy's case, but Russia's Prosecutor-General office said the constitution prevented it from extraditing Russian citizens.

"No one should be under any doubt about the seriousness with which we regard this case. Murder is murder," Prime Minister Tony Blair's spokesman said.

Lugovoy denied the accusation and told Itar-Tass news agency: "I consider this decision politically motivated."

He added: "I did not kill Litvinenko, have nothing to do with his death, and can prove with facts my distrust of the so-called evidence collected by Britain's justice system."

The murkiest case of murder and espionage since the Cold War had already strained diplomatic relations and the extradition move looked certain to aggravate tensions further.

Sticking to rules

Blair's spokesman stressed Britain had important political and economic ties with Russia. "This doesn't in any way obviate the need for the international rule of law to be respected, and we will not in any way shy away from trying to ensure that happens in a case such as this," he said.

Russian prosecutors said they would give their full attention to any charges against Lugovoy once they received official documents from Britain, and opened the possibility he could be tried in his homeland.