Deshchytsya, on a visit to Berlin, said Ukraine hopes the declarations made by Russian officials about the withdrawal "will not remain just declarations."
Ukraine's border guard service earlier on May 20 said that Russian forces had left the area within 10 kilometers of the border shortly after Russian President Vladimir Putin ordered the troops to withdraw.
Putin ordered the troops to pull back on May 19, six days before Ukraine holds a presidential election.
NATO estimates Russia had amassed 40,000 troops near the border as pro-Russian separatists seized control of several towns in eastern Ukraine.
But Ukrainian authorities stopped short of confirming Moscow's claims that a full withdrawal has been made.
The Pentagon said on May 20 that it had seen no evidence Russia has withdrawn its 40,000 troops.
Ahead of the May 25 presidential election, Ukrainian authorities are scheduled to hold a new round of "national dialogue" today aimed at ending an insurgency by pro-Russian separatists who control dozens of cities and towns in eastern Ukraine.
The talks are to take place in the southern city of Mykolayv.
Meanwhile, Ukraine’s richest man, Rinat Akhmetov, has denounced pro-Russian rebels as bandits who might create "genocide."
Akhmetov, seen as a key powerbroker in Ukraine’s crisis, condemned the insurgency and called on Ukrainians to stage peace rallies.
Prince Charles 'compared Russian actions to Nazis' http://t.co/xLfLm4ERdd
— bruce springnote (@BSpringnote) May 21, 2014
#EuroMaidan six month anniversary today. Here is a good timeline of the events leading to Yanukovych leaving Ukraine. http://t.co/3V8geeJcEq
— Anders Östlund (@andersostlund) May 21, 2014
Putin's press secretary Dmitry Peskov tells Sky News "he knows nothing" about the comment made by Prince Charles.
— Yulia Bragina (@YuliaSkyNews) May 21, 2014
The detention on May 18 of Oleg Sidyakin and Marat Saichenko prompted a furious reaction from officials in Moscow, who demanded their immediate release.
But U.S. State Department spokeswoman Jen Psaki said on May 20 that Ukrainian security services reported the two had "manned portable antiaircraft missiles in the trunks of their cars" when they were detained.
Psaki said Washington condemns “the unlawful detention of journalists in any capacity.”
But she said Kyiv is questioning whether the two "were actually journalists."
LifeNews is owned by News Media Holding – a private Russian firm controlled by Kremlin-loyalist Aram Babrelyanov and whose major shareholders include members of Russian President Vladimir Putin’s inner circle.
Everyone seems to be detaining the media now, including Ukraine, the separatists AND the Russian Federation https://t.co/o7FHYTfIcd
— Simon Ostrovsky (@SimonOstrovsky) May 21, 2014
Hmm. Akhmetov may have left it too late. @courtneymoscow finds little enthusiasm for protest amongst his workers. http://t.co/2e1YaijEOa
— Roland Oliphant (@RolandOliphant) May 21, 2014
Militia claims that they have arrested 7 shooters responsible for the 20 February killings on #euromaidan with more to come
— bruce springnote (@BSpringnote) May 21, 2014
Ukraine bans entry to @RT_com crew sent to cover presidential election http://t.co/NdH2eXMVWl
— Maxim Eristavi (@MaximEristavi) May 21, 2014