Ministry spokeswoman Lilia Klochko said the ceremony, initially scheduled for today, would take place either on 23 January or 25 January.
Klochko gave no reason for the delay and Gazprom has not confirmed the postponement.
The Ukrainian parliament voted on 19 January to dismiss Fuel and Energy Minister Ivan Plachkov and another cabinet member for their alleged role in helping to strike the controversial gas deal.
An aide to President Viktor Yushchenko said on 20 January that the vote was not legally binding.
Yushchenko has defended the gas deal, under which Ukraine agreed to pay nearly as twice as much for Russian gas as it does now.
(Unian, Interfax-Ukraina)
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Klochko gave no reason for the delay and Gazprom has not confirmed the postponement.
The Ukrainian parliament voted on 19 January to dismiss Fuel and Energy Minister Ivan Plachkov and another cabinet member for their alleged role in helping to strike the controversial gas deal.
An aide to President Viktor Yushchenko said on 20 January that the vote was not legally binding.
Yushchenko has defended the gas deal, under which Ukraine agreed to pay nearly as twice as much for Russian gas as it does now.
(Unian, Interfax-Ukraina)
RFE/RL Belarus, Ukraine, And Moldova Report
RFE/RL Belarus, Ukraine, And Moldova Report
SUBSCRIBE For weekly news and analysis on Belarus, Ukraine, and Moldova by e-mail, subscribe to "RFE/RL Belarus, Ukraine, And Moldova Report."