US and Russia trade accusations over Ukraine

US President Joe Biden has phoned Russia's President Putin to stress support for Ukraine's territorial integrity, amid concerns about Russian troops on the border. What is Moscow's strategy and what can the West deliver? Also in the programme: President Biden is to withdraw US forces from Afghanistan by September 11th; and the US drugs regulator is recommending suspending the use of the Johnson and Johnson vaccine because six recipients out of nearly seven million have developed rare blood clots. (Photo: Russian units have been on exercises in Russian-annexed Crimea. Credit: Getty Images)