Ukrainian presidential adviser Podolyak said that fighting against Russia could only end when Kiev regained the Crimea peninsula.
Russia has started fighting against Ukraine since 2014 when controlling Crimea.
Mr. Podolyak then continued to post the tweet emphasized that Crimea and Donetsk or Kherson were not part of Russia and Ukraine with full rights to liberate their territories, using any weapons.
Advisor of the President of Ukraine, Mykhailo Podolyak, at Kiev on April 19.
Vadym Skibitsky, representative of the Ukrainian Military Intelligence General, on July 16, warned that the country's forces could use Himars jet to ambush Russian military facilities on the Crimea peninsula.
Ukraine has committed to the US without using Himars to raid targets in Russia, but Kiev does not consider Crimea as a territory of Russia.
Crimea peninsula.
The Russian - Ukrainian conflict has not shown signs of cooling down even though it has entered the sixth month.
The Western military judges the progress of the Russian forces and the separatist faction in eastern Ukraine are slowed down due to their severe casualties.
Ukraine publicly intended to counterattack in the South, forcing Russia to transfer forces to cope, creating opportunities for Kiev to balance the situation in the East.
Conflict with Russia caused Ukraine budget to exhaust, while Western aid drip, causing Kiev to struggle to find money to maintain the economy.