Bismarck had a long-term policy of preserving the peace in Europe, and the growing competition between Russia and Austria–Hungary for dominance over the Balkans threatened that peace. Bismarck felt that an agreement with Russia was essential to prevent a Russian alliance with France - he always had the policy of keeping France isolated diplomatically in order to avoid a two-front war with Germany fighting both France and Russia. Bismarck risked the expansion of the Russian sphere of influence toward the Mediterranean and diplomatic tensions with Vienna.