The formula of Ukraine's cooperation with the Customs Union in the 3+1 format is still relevant, an advisor to the Ukrainian president, Volodymyr Zubanov, has said.

"[President] Viktor Yanukovych said that relations with the Customs Union on the current conditions - the charter and the Eurasian Commission as an executive body – don't suit our state and our vision for the development of Ukraine. And we can consider the question only as a 3+1, and we're gradually walking this path," he said on Channel 5 on Thursday evening.

Zubanov added that the signing by Ukraine of a memorandum envisaging its participation in the work of the Customs Union would not mean its future accession to the Eurasian Union.

Batkivschyna MP Andriy Senchenko, in turn, said on Channel 5 said that the desire of the authorities to get closer to the Customs Union is triggered by the difficult economic situation and that the authorities are trying to "convert the national independence of Ukraine into monetary gain."

As reported, Ukrainian President Viktor Yanukovych said that a memorandum on Ukraine's participation in the work of the Customs Union would be signed in Minsk on May 31 at a meeting of the CIS council of heads of government.

According to Russian First Deputy Prime Minister Igor Shuvalov, the memorandum will allow Ukraine to participate in all formats of the Eurasian Economic Commission and the Supreme Economic Council. Since observer status is not envisaged in the Customs Union, this status could be granted to Ukraine only after the signing of an agreement on the creation of the Eurasian Economic Union, which is scheduled for January 1, 2015.