FAM of Ukraine voiced protest to Russia because o the visit to Crimea by the President of RF Vladimir Putin on November 18, 2017. It was said in the official data of FAM of Ukraine that was posted on the side of the Ministry.
Ukrainian side considers this visit in one range with other trips of other Russian politicians to Crimea and Sevastopol as rude violation of state sovereignty and territorial integrity of Ukraine.
Foreign Affairs Ministry of Ukraine considers Crimea and Sevastopol as a part of Ukraine.
Remember that the referendum on separation was held in Crimea in March 2014, and more than 90% of population voted for the separation from Ukraine and joining of Russia.