KIEV, Jan. 4 – Swedish Foreign Minister Carl Bildt has described a statement made by a representative of the Russian Foreign Ministry concerning Kiev's relations with the Customs Union as serious economic blackmail.

"It's obvious here that Russia is using heavy economic blackmail to force Ukraine to change its political course," he wrote on his page on Twitter on Friday, adding that Kiev then reacted to statements by Russia.

On January 1, in an interview with Interfax, the director of the Russian Foreign Ministry's economic cooperation department said, Alexander Gorban, said that Russia was not going to lower the price for its gas for Ukraine unless it joins the Customs Union of Russia, Belarus and Kazakhstan.