European Union policymakers say dealing with an increasingly assertive, energy-rich Russia is the 27-nation bloc's biggest foreign-policy challenge.
The EU is divided over the best way to engage Moscow
Relations between Europe and Russia contain a "level of misunderstanding or even mistrust we have not seen since the end of the Cold War," EU Trade Commissioner Peter Mandelson said recently.
Javier Solana, EU foreign and security policy chief, has also appealed for "calm" in EU-Russia relations, arguing that given Moscow's global clout and vast energy resources, the two sides must forge a "deep and solid relationship."
Putin has spoken his mind loudly to the EU recently
Russia's President Vladimir Putin has been angered by EU criticism of Russia's human rights record, hardline policies in Chechnya and repression of dissidents and reporters.
In turn, Europeans are unhappy with Russia's strident anti-Western tirades, including harsh criticism of EU newcomers Poland and the Czech Republic for their plans to host parts of a US missile shield and of Estonia's recent decision to remove a Soviet-era memorial from central Tallinn.
Hardball against soft power
Officials in Brussels are most worried, however, about the growing rift within their own ranks on how best to deal with the bloc's most powerful -- and most difficult -- neighbor.
EU governments are split between those who want to play hardball with Russia on issues like energy and human rights and others keen to woo the country by using Europe's traditional "soft power" tools of aid, trade and diplomacy.
To some extent, the EU divide is based on history and geography. Russia's direct EU neighbors and former satellites -- including the three Baltic states and five Eastern European countries which
joined the bloc in 2004 -- are lobbying hard for a tough stance against their former Soviet patron, arguing that Moscow's renewed imperial ambitions threaten its neighbors.
They are convinced of Russia's determination to use its energy resources as a political weapon -- a sentiment that has grown since the brief cut-off of Russian gas supplies to Ukraine in January 2006.
The EU currently depends on Russian natural gas for 25 per cent of its requirements, and the Ukrainian cut-off disrupted deliveries to several western European states.
There are fears Russia is using its oil as a political weapon
EU newcomers have adopted a tough stance. Poland, for instance, has refused to give the go-ahead to launch negotiations on a long-sought EU-Russia cooperation pact.
President Toomas Hendrik Ilves of Estonia insisted recently that the "two European goals are incompatible: European integration and appeasement of a rogue-like and threatening Russia."
And a recent Czech foreign ministry statement warned Moscow that that it is up to each state to decide how to cope with the past: "Pressure exerted by another state is, as a rule, counterproductive."
Some favor strategic partnership
But others, including powerful players like Germany, the United Kingdom, Italy and France, are pushing for a "strategic partnership" with Russia, covering joint efforts to combat climate change, forge stronger energy links and cooperation with nearby countries, including Ukraine, Georgia, Belarus and Moldova.
Those seeking engagement with Russia advise patience, arguing that Moscow's readiness to confront the West stems from increased wealth and a desire to reassert its influence as a world power.
EU trade chief Mandelson says Europeans must be more understanding of Russia's vulnerabilities. Moscow feels "increasingly encircled by the West and wedged up against a rising China," he argues.
Solana has pointed out that the West needs Russian help in solving an array of problems, including efforts to convince Iran to suspend uranium enrichment and the search for a final settlement for the breakaway Serb province of Kosovo.
Merkel favors the voice of reason with Putin
It's not just a one-way street, say EU officials. While Europe is reliant on Russian energy, Moscow depends on energy sales in Europe and needs European investments in its natural-gas sector.
EU and NATO officials admit that dealing with Russia will be difficult in the months leading to the spring 2008 presidential election that will determine Putin's replacement.
That means more fireworks at the next EU-Russia summit scheduled to be held on October 26 in Lisbon, with Portuguese Prime Minister Jose Socrates in the chair.