Russia wants to negotiate a "serious" pact governing its relationship with the European Union but not one overburdened with detail, President Dmitry Medvedev told Reuters in an interview.

Speaking ahead of a key summit between Russia and the EU in Siberia starting on Thursday evening, Medvedev said Russia saw itself as "a major European state ... which defines itself as part of Europe" but avoided any criticism of EU member states.

The summit is expected to launch negotiations on a much-delayed partnership agreement covering the occasionally testy relations between Moscow and its western neighbours, some of them unwilling former Soviet allies.

Although he described the EU as a "comfortable" partner for Russia, Medvedev told Reuters that its guiding principle of solidarity could "at times create problems for the functioning of EU mechanisms".

This was a reference to the 18-month delay in launching the partnership talks after first Poland and then Lithuania raised objections over bilateral problems with Russia.

Medvedev pointed to Ireland's rejection of the Lisbon Treaty as an example of how the EU's need for complete internal unity on decisions could damage the bloc's own interests.

"I don't consider the European Union a hard or difficult partner," he said. "But it is a partner which periodically encounters difficulties."

EU states are nervous about the bloc's dependence on energy from Moscow - the supplier of a quarter of Europe's gas. They also want to use the partnership talks to improve protection for EU companies investing in Russia's unpredictable business world.

But Medvedev said Moscow did not want to become tied down with large amounts of fine print in a document which should serve only as a framework for other, more detailed pacts.

"It must be a serious document but at the same time not burdened with absolutely concrete things; to a large degree it should be a framework agreement that will set out the basic positions for development in the years ahead," he said.

He named the key priorities for relations with the EU as political cooperation, energy cooperation and cooperation in fighting crime, but did not go into detail, saying these issues were everyday business.

Medvedev's predecessor Vladimir Putin frequently attacked the Baltic states over what he termed their tendency to rewrite history to underplay the role of the Soviet Union in defeating Nazism and to neglect the rights of Russian citizens.

But Medvedev avoided any direct mention of controversial topics in relations between Russia and EU members.