"It's important to send a very clear message that if there is further destabilization in Ukraine then there should be further wide ranging measures taken and we've agreed tonight that we will task the European Commission to draw up those possible measures. That is progress and the world will be able to see that," he added.
The Prime Minister of Finland, Jyrki Katainen, told CNBC he was confident that adding 12 names to the target list would deliver a strong message.
"When looking at the reaction of the oligarchs, it is a strong message. We have two other messages. First of all, we need to get the Russians around the negotiation table and also we need a monetary mission to the Ukraine because we want to avoid expulsion of instability," he added.
Sweden's Reinfeldt also said although the EU needed to demonstrate that it was prepared to get tough on Russia, they did not see this as a long-term solution: "The long-term solution must be an open Europe and open Russia, trading with each other."
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Following the summit, the EU also announced that they were considering sending an observer mission to Ukraine if the Organization for Security and Cooperation in Europe fails to put forward its own mission.
On Monday the U.S. announced sanctions on Russian, Ukrainian and Crimean individuals and involved a bank, targeted several individuals close to Putin in retaliation for his military seizure of Ukraine's Crimea region. Putin has since retaliated by imposing sanctions on nine U.S. officials and lawmakers.
— By CNBC's Katie Holliday: Follow her on Twitter