Just over one week since US President Donald Trump held a much-anticipated summit with his Russian counterpart Vladimir Putin in Alaska, US efforts to bring an end to the war in Ukraine have stalled. On Friday, Mr Trump renewed a threat to impose sanctions on Russia if there were to be no progress towards a peaceful settlement in Ukraine in the next two weeks. However, the Kremlin has indicated that it has no plans to arrange a meeting between Mr Putin and Ukrainian President Volodymyr Zelensky,