Cyber-attack is brutal reminder of the Russia problem facing Joe Biden

Analysis: new president must find a way to contain such hyper-aggressive behaviour from Moscow

It is Joe Biden's biggest foreign policy headache. As well as confronting the Covid pandemic, the president-elect has to deal with a more familiar problem: Russia. Moscow's meddling in the 2016 US presidential election cast a shadow over US politics for four long years.

And now the Kremlin appears to have struck again. This week details emerged of an unprecedented cyber-attack against US government departments. Beginning in March, suspected Russian hackers penetrated Washington's signature institutions.