European Union leaders will discuss sanctions against Russia ahead of an emergency summit meeting, the French foreign minister said today, as western leaders increased diplomatic pressure on Moscow.

When asked what measures the west could take against Russia in the crisis over Georgia, Bernard Kouchner told a press conference in Paris: "Sanctions are being considered."

He gave no details, but the threat reflects western impatience at Moscow after its invasion of Georgia and its recognition of Georgia's breakaway provinces, South Ossetia and Abkhazia, as independent.

Despite Kouchner's comments, it will not be easy to reach consensus on sanctions within the EU as some states will be unwilling to jeopardise mutually beneficial relations with Moscow. In particular, the German chancellor, Angela Merkel, is unlikely to support any moves that could damage relations and interrupt the flow of gas and oil to Europe.

It is the first time that France, which prides itself on good relations with Moscow, has raised the possibility of sanctions or other measures in the standoff between the west and Russia.

"I do not want to prejudge the issue before the EU summit on Georgia has taken place," Kouchner said. "But we will work hard with our 26 partners to draft a strong statement that signifies our refusal to accept the situation in Georgia. France does not support breaking off relations with Russia. This will have to be sorted out through negotiation. This will take time, we are not deluding ourselves."

Analysts say the EU is not contemplating the type of sanctions imposed on Iran or Zimbabwe, which include arms embargoes and travel bans. But the EU is likely to postpone talks on a new partnership and cooperation agreement with Russia scheduled for September, or at the extreme, break them off indefinitely. Similarly, France, which is scheduled to host a biannual meeting of the EU-Russia council in Nice in November, may decide it is not the time to roll out the red carpet for the Russians.

Recent moves to forge security ties with Russia appear doomed. Moscow has expressed interest in having a role in attempts to forge a common European defence policy. Russia had offered the use of helicopters to the EU as an incentive for being included.

On the economic front, analysts speculated the EU could take a closer look at the activities of Gazprom, the Russian energy giant in Europe. Gazprom gets 70% of its profits from sales to EU countries, and the size of the market gives the EU important leverage. The flipside is that Europe, particularly Germany, depends heavily on these supplies.

As to support for Georgia, the EU could improve visa access for its citizens, give Tbilisi greater trace access to the EU, or hold an EU-Georgia summit.

The Russian foreign minister, Sergei Lavrov, dismissed the idea of sanctions as the product of a "sick imagination".

"My friend Kouchner also said that we will soon attack Moldova and Ukraine and the Crimea ... But that is a sick imagination and probably that applies to sanctions as well," he told reporters at a security meeting in the Tajik capital, Dushanbe. "I think it is a demonstration of complete confusion."

France, which brokered a ceasefire between Russia and Georgia, has called an emergency meeting of EU leaders on Monday to discuss the most serious rupture between Russia and the west since the end of the cold war.

Russia failed to get the robust support it was seeking from its allies on the Shanghai Cooperation Organisation (SCO), a security group that includes China and that Russia help set up. After a meeting in Dushanbe, attended by the Russian president, Dmitry Medvedev, the group condemned the use of force and called for respect for every country's territorial integrity.

"The SCO states express grave concern in connection with the recent tensions around the South Ossetian issue and urge the sides to solve existing problems peacefully, through dialogue, and to make efforts facilitating reconciliation and talks," the final declaration said.

Britain said it would not accept the redrawing of Europe into spheres of influence. David Miliband, the foreign secretary, said such concepts were "anathema" and belonged to the second world war era of Yalta. He rejected the argument that Nato was an offensive alliance seeking to encircle Russia.

The 1945 agreement at the Yalta conference, between the leaders of Britain, the US and the Soviet Union, saw the allied powers accept that eastern Europe fell into Moscow's sphere of influence.

Miliband's comments on BBC Radio 4's Today programme followed a tough statement signed by himself and the foreign ministers of the US, Canada, France, Germany, Italy and Japan deploring Moscow's "excessive use of military force" in Georgia.

The statement, described as an "unprecedented step" by the Foreign Office, followed a warning from Miliband delivered in Kiev, the Ukrainian capital, to Medvedev that he bore a "big responsibility" not to provoke a new cold war.

The foreign ministers said Moscow's recognition of South Ossetia and Abkhazia violated Georgia's integrity and sovereignty. "We ... condemn the action of our fellow G8 member. Russia's recognition of the independence of South Ossetia and Abkhazia violates the territorial integrity and sovereignty of Georgia and is contrary to UN security council resolutions supported by Russia."

In his interview, Miliband rejected the notion that his visit to Ukraine had been provocative. He said he went there because it was important to say to a friendly country that "we support their democratic choices". The foreign secretary reiterated Britain's support for Ukraine's wish to be in Nato and rebuked Russia for treating its neighbours as if they were either "enemies or vassals".

Miliband, tipped as a future Labour party leader and potential prime minister, went to Kiev to deliver a speech flying the flag of western democracy on Russia's doorstep, while seeking to avert a new crisis on the Crimean peninsula, home to an ethnic Russian population and Moscow's Black Sea fleet.

The speech represented the strongest criticism of the Kremlin from a leading European government official in years, delivered in a country that is Russia's neighbour and which Russians view as the cradle of their civilisation.

Miliband declared a turning point had been reached in Europe's relations with Russia, ending nearly two decades of relative tranquillity. He said Tuesday's decision by Medvedev to recognise Abkhazia and South Ossetia as independent represented a radical break and a moment of truth for the rest of Europe.

"[Medvedev's] unilateral attempt to redraw the map marks a moment of real significance," Miliband said. "It is not just the end of the post-cold war period of growing geopolitical calm in and around Europe. It is also the moment when countries are required to set out where they stand on the significant issues of nationhood and international law."