Visa requirements for Ukrainian citizens
For traveling to certain countries, Ukrainians do not need to use a passport, as they may use their Ukrainian identity card or internal passport.
Documents which give the right to leave Ukraine and to enter Ukraine and certify the identity of a citizen of Ukraine while staying abroad are:It's important to know, that the special rules of arriving in a particular country should be studied carefully. Thus, in most countries that do not require visas or issue visas, upon arrival you must have a passport, which is valid for at least 3 months from of arrival to this country.
Visa policy of Ukraine
The Autonomous Republic of Crimea was annexed by Russian Federation after its military intervention of 2014. 
On 4 June 2015 the Government of Ukraine has adopted the resolution No. 367 "About the statement of the Order of entrance on temporarily occupied territory of Ukraine and departure from the territory". According to the document, entrance of foreigners and persons without citizenship on temporarily occupied territory of Ukraine and departure from the territory is carried out through checkpoints according to passport documents and the special permission given by territorial authority, which, however, is not issued to regular visitors. Hence, most foreigners can only enter Crimea from Russia, whereby no border control is carried out and no trace of the entry left in the person's passport. Nevertheless, if somehow discovered doing this, such as by trying to enter "mainland" Ukraine from Crimea, Ukrainian law provides that tourists having entered Crimea from Russia can face an entry ban and/or imprisonment.