London  - Russia and Britain attempted Monday to mend strained relations in discussions in Moscow, ranging from Iran's nuclear programme to continuing bilateral tensions over the poisoning of former spy Alexander Litvinenko in London three years ago.

In what was the first visit of a British Foreign Secretary to Russia in five years, David Miliband emerged from wide-ranging talks with his Russian counterpart, Sergei Lavrov, praising the growing "common ground" in relations between the two countries.

The discussions had been "substantive and productive and were marked by "mutual respect," said Miliband, while stressing that neither side intended to "paper over our differences."

Both Lavrov and Miliband urged Iran to give a "prompt response" to international proposals concerning the future of its nuclear programme, which envisage sending Iran's low-enriched uranium to Russia and France for further processing.

A statement on the talks released by the Foreign Office in London said that the situation in Afghanistan, the Middle East conflict and "European security" were among the topics discussed.

"As a result of our talks, I think we can say that not only do we understand each other better, but we are going to find ways to work together better," Miliband told a news conference.

The cultural and business links that are growing, I think, are testimony to the importance of the UK-Russia relationship," Miliband said.

"That is reflected now at governmental level - not just on issues of the economy and foreign policy, but also on energy, climate change and other issues."

While both sides were agreed that existing differences should not be swept under the carpet, they would also not allow them to "block cooperation where possible."

"I think it is very important that countries like Britain and Russia show leadership on the international stage," said Miliband.

He added that Britain wanted relations between Russia and the European Union to "develop in a strong and sensible way."

However, it was quite clear that bilateral relations remained strained by the Litvinenko affair.

Miliband again urged Russia to hand over for trial Andrei Lugovoi, the chief suspect in what he called the "horrific murder" by radioactive poisoning of London-based Litvinenko in November 2006.

"We can continue to be absolutely open about the importance that we attach to (these issues) and we don't trade them off," said Miliband.

"Instead, we say there are other areas where there is more common ground and we are determined to work together."

But Lavrov, while describing his talks with Miliband as "positive and productive," insisted that the Russian constitution forbade the extradition of its citizens.

"The demands that we basically change our constitution are absolutely unrealistic," he said.(dpa)