What issues is Russia facing in Ukraine war?

As Ukraine prepares for a much anticipated counter-offensive against Russian forces, BBC Analysis Editor Ros Atkins looks at the challenges facing Russia’s military.

Since Russia's President Vladimir Putin began the invasion of Ukraine, thousands of civilians and combatants have been killed or injured, cities and towns have been destroyed in fighting, and nearly 8.2 million Ukrainians have been registered as refugees in Europe, with 2.8 million of them in Russia.

In the past few days, President Volodymyr Zelensky has been on a European tour, in which he has been promised several billion dollars' worth of military equipment by Western allies, including UK Prime Minister Rishi Sunak and President Emmanuel Macron of France.