Tightening of sanctions could undermine the meeting on Thursday, when it will become clear whether diplomatic efforts should continue or whether the sanctions need to be stepped up, Erjavec told the STA in a phone conversation while the meeting was still ongoing.

He said Slovenia advocated a "thorough analysis" of what the EU wants to achieve with economic sanctions, which would be the second step in the escalation after an expansion of the current list of persons banned from travelling to the EU.

While the meeting in fact did not bring a decision on economic sanctions, a second expansion of the banned persons list was agreed on in face of the escalation of the situation in the east of Ukraine.

The ministers also held a debate in efforts to secure a concerted EU reaction to possible restrictions to gas supplies to Europe due to the situation in Ukraine.

Eighteen member states, including Slovenia, recently received a letter from Russian President Vladimir Putin expressing concern over Ukraine's debt stemming from gas supplies, in which Putin also suggests gas shipments to Europe could be affected.

According to Erjavec, everyone agrees that letter constitutes "inadmissible pressure" that requires a reaction, but it is not yet clear who will formally reply.