Ukraine has enough gas in underground storage to meet its energy needs until December, the chief executive of Ukraine's state gas company Naftogaz said.
Arseny Yatseniuk said the country has 14 billion cubic meters of gas stored.
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The study looked at the development of 422 children over the course of eight years.
The president said they will come into force if China refuses to change its practices.
Laura Bush called the policy “cruel” and “immoral”.