Moscow/Tbilisi - Russian President Dmitry Medvedev has stressed in a telephone call to British Premier Gordon Brown that Moscow wants a "constructive dialogue" with the European Union irrespective of the Georgia conflict, it was reported Saturday.

He told Brown that Russia welcomed the deployment of Organisation for Security and Cooperation in Europe (OSCE) observers in the conflict regions of Georgia, Interfax news agency reported.

He also renewed Russian accusations that the Georgian leadership under President Mikheil Saakashvili was responsible for the southern Caucasus conflict.

It was "aggression" from Tbilisi towards its separatist regions of South Ossetia and Abkhasia that had made it impossible for these regions to live in peace within Georgia.

Georgian media reports meanwhile quoted Saakashvili as saying Tbilisi was to introduce tougher laws to stop Georgia being "destabilised" following the recent invasion by Russian troops.

Saakashvili was speaking late Friday during a visit to the Black Sea town of Poti where there was still a Russian troop presence, the reports said.

Saakashvili had given no details of what measures were being introduced, but had stressed that "citizens' rights" would not be affected.

Saakashvili again accused Russia of having planned to overthrow the Tbilisi leadership by force - a claim once again denied late Friday by Russian Prime Minister Vladimir Putin.

The claim, he told a German television interviewer, was "an outright lie" - but he also said he believed Saakashvili should step down.

"He ought not to be in public office," said Putin. "He ought to resign immediately."

Putin also called for the European Union to take a "reasonable attitude" on the Caucasus conflict at an EU summit in Brussels next Monday, and not impose sanctions.

"The issue of sanctions is not something we don't care about," he said. "We hope that reasonableness prevails."

Putin said Russia intended to withdraw its soldiers from the buffer zone they had take over in uncontested Georgian territory as soon as the crisis de-escalates.

Putin's remarks came as Russian and European officials tried to curb escalating tensions as diplomats on both sides spoke out against sanctions.

Sanctions are among measure set to be discussed in Brussels Monday by EU leaders furious over Moscow's slow withdrawal of troops from Georgia.

But EU diplomats also expressed worries that Russia might use its control over oil supplies as a political tool, such as in the past when it once cut off the flow of oil to the Ukraine in a pricing dispute.

Moscow's ambassador to the EU Vladimir Chizhov urged against sanctions Friday.

"I won't bet on it, but, at least, I hope that European leaders will be able to rise above their emotions and seriously take stock of the perspective of a strategic partnership with Russia," Chizhov was quoted by news agency Interfax as saying in Brussels.