As his attack falters, Putin could become more brutal – and even more irrational | Mathieu Boulègue

Russia is starting to reassess its objectives. Expect a return to tactics seen previously in the likes of Chechnya and Syria

Russian military operations against Ukraine are moving beyond the initial period in which the aim was creating quick superiority. Many observers have been surprised at Russia's failure to achieve early gains and the defeats it has suffered.

The heroism and resistance of Ukrainian forces have initially constrained Russia. Ukrainian command and control systems - the ability to communicate, move and fight - are still functioning. Ukraine's air defence is still standing, thus denying Russia the superiority Moscow would have hoped to achieve quickly.

Mathieu Boulegue is a research fellow with the Russia and Eurasia programme at Chatham House, the Royal Institute of International Affairs, London