European Union nations postponed a decision on December 9 on renewing the bloc's economic sanctions against Russia after Italy called for a debate on the matter.
Ambassadors from the 28 member states had been expected to agree on a six-month extension of the sanctions, which expire at the end of January, at a meeting in Brussels without any debate.
But Rome said the matter should be decided by EU leaders who meet next week in Brussels.
Italy and some other southern European states have shown some reluctance to maintain the sanctions, which have packed a powerful economic punch.
The sanctions, which were imposed over Moscow's annexation of Crimea and support for pro-Russian separatists in eastern Ukraine, target Russia's banking, oll, and defense industries. They were originally introduced in mid-2014.
Poland, the Baltic states, and some other Eastern European nations have taken a harder line on maintaining the sanctions.