(CNN) -- After hours of chewing over how to deal with Russia's annexation of Crimea, EU heads have added a further 12 individuals to their blacklist.
The list -- adding to an initial 21 person-one long penned on Monday-- is to be released on day two of their Brussels summit. Its first incarnation, presented to European leaders for discussion on Thursday night, included figures close to the Kremlin, an EU union official said.
Notable on the list are Valentina Matvienko, speaker of Russia's upper house, as well as the country's deputy prime minister, Dmitry Rogozin, CNN has learned.
The inclusion of Rogozin, in particular, the official said, was almost blocked by Cyprus and Slovakia. They were fearful of the fallout from naming one of Russia's top politicians.
Yet there was a sense that, as an outspoken critic of the West, Rogozin -- like others targeted -- deserved reprimand, the source said.
Malta also expressed concern about an unnamed candidate for sanctions, but withdrew its objection.
CNN also understands that family members -- thought to be key to the efficacy of any measures -- were not considered amid questions about the legality of such a move and the viability of placing travel bans on individuals, who in some instances are already residents inside the EU.
Those expecting swathes of Russian industry to feel the brunt of Europe's indignation may be disappointed. For sources say that no chief executives of the country's largest companies, like Gazprom, Rosneft and VTB Bank, will feature on the additional file.
Russian President Vladimir Putin's chief of staff Sergey Ivanov and his minister of defense Sergey Shoigu were not written into the documentation, prepared for Europe's leaders ahead of their meetings, for fear of sending a bellicose signal to Russia.
Though, because of their stature, there was debate about placing them back on, the aide said.
Advisers to the Russian president, Vladislav Surkov and Sergey Glazyev, both of whom also face US sanctions, were set to be targeted by the EU as well.
Some subject to EU sanctions also find themselves on two lists released by the US this week. Europe has had difficulty in matching America's action against Russia on Ukraine because each move requires ratification by all 28 member states.