On July 7 , while the unsuccessful hunt for fugitive Bolsheviks continued, Prince Lvov resigned as leader of the Provisional Government. He was replaced by Kerensky. This had nothing to do with either the July uprising or the failed offensive. Five days earlier, Kadet ministers had resigned in protest at a decision to allow Ukraine a degree of autonomy.
Both liberals and socialists in the reconstituted Provisional Government wanted to keep the Russian empire together. They had accepted in March that after the war Poland, now behind German lines, would break away to become fully independent, but they were determined to hold on to the Grand Duchy of Finland, the Baltic provinces and Ukraine. their view was that the grievances and aspirations of national minorities were purely the product of Tsarist oppression, above all the ‘russification’ programmes introduced under Nicholas II which had discourages any diversity of culture or language. A few limited concessions to autonomy were thought to be sufficient.
…Russians in Kiev never expected the Ukrainian forces to put up much of a fight. Deliberately ignoring the reality of Ukrainian culture and history, they had taken Ukrainian patriotism as little more than a joke.
That is from the new and excellent Anthony Beevor book, Russia: Revolution and Civil War 1917-1921.