Russian Prime Minister Dmitry Medvedev has said tensions between Russia and the West have reached Cold War levels.
Other leaders also warned of dangerous divisions within Europe.
Speaking at the Munich Security Conference on Saturday, Medvedev said the world had "slid into a new period of Cold War" as differences grew between the West and Russia over conflicts in Syria and Ukraine.
"Almost every day we are accused of making new horrible threats either against NATO as a whole against Europe or against the US or other countries," he told delegates at the meeting in the southern German state of Bavaria.
Medvedev said, however, that in the face of the challenges currently facing the world, such as regional conflicts, terrorism and the migration crisis, Russia needed to be regarded as a partner.
He added that differences between Moscow and the rest of the world were not unbridgeable.
"Our positions differ, but they do not differ as much as 40 years ago when a wall was standing in Europe," he said, and cited several instances of agreements that had been achieved since then, including on issues such as disarmament, Iran's nuclear program and piracy.
The Russian prime minister accused the West of expansionist policies toward formerly Soviet-ruled eastern Europe since the end of the Cold War, saying they were deepening the rift with Moscow.
Medvedev also called into question the sagacity of sanctions imposed on Russia by the West over its annexation of Crimea and its support of pro-Moscow rebels in eastern Ukraine, saying they damaged both sides and calling instead for global cooperation to combat what he called a widening economic crisis in the world.
In responding to questions posed after his speech, he also denied accusations that Moscow was attacking civilians in Syria as part of its military offensive there to prop up the government of President Bashar al-Assad.
Russia's military operations in Syria are a cause of concern in many Western countries, who fear that civilians and "moderate" rebels opposed to Assad's rule might be targeted.
Moscow says its airstrikes aim only to combat radical Islamist forces such as "Islamic State."
Earlier, French Prime Minister Manuel Valls also mentioned Russia's bombing campaign in Syria, reiterating the accusation that civilians were being killed in the attacks.
Valls said Moscow's airstrikes were an obstacle to efforts to bring peace to the country, which has been wracked by five years of civil war.
Valls also warned that European unity was under siege amid economic challenges and the difficulties posed by a massive influx of refugees and migrants, mostly coming from the Middle East and Africa.
"The European project can go backwards or even disappear if we don't take care of it," he said.
"If Europe doesn't show it can respond, not only to economic challenges but also to security challenges, then the European project will be finished because the people won't want it any more."
German Foreign Minister Frank-Walter Steinmeier also called for more European unity amid "stormy times."
"External crises and inner strength are obviously inseparable," he said.
"We can defy the storms that are raging outside the EU only if we stand together in the EU."
The remarks come as the EU's Schengen zone, which allows free travel between member states, comes under increased threat as ever more countries close their borders in view of the number of refugees and migrants attempting to enter the bloc.