A fresh package of restrictive measures towards Russia the EU Foreign Affairs Council is set to discuss on Thursday is likely to expand blacklists, a European diplomat told Interfax on Wednesday.

He said that was an option and more individuals and companies might be added to the blacklists.

In fact, the EU foreign ministers will be considering a whole package of possible restrictive measures and the concrete measures and their elements will depend on the decisions they make.

The diplomat gave an evasive answer to the question about Russia's possible disconnection from the SWIFT system. He said he personally believed in the existence of such a possibility but it was an extremely serious one and added that everything depended on the events in Ukraine.

The European Union is disappointed with escalating tensions in southeastern Ukraine, the source said, noting that what they had been seeing in Ukraine was a brink of war.

Speaking of the situation the way most EU countries look at it, they are extremely disappointed that the minor progress made in Berlin has obviously been marred, and a major failure is looming, he said.

The diplomat emphasized that the EU would respond to the escalating situation in Ukraine one way or another.

Another diplomatic source, an unnamed senior European diplomat, told Interfax that one should not expect stronger economic sanctions against Russia in the near future although a lot would depend on the events evolving in eastern Ukraine.

He said a new package of sanctions was being prepared.

However, the package is likely to expand the blacklist of individuals and companies which would be barred from visiting the European Union and would have their assets frozen, he noted.

The diplomat said the task was not easy: the leaders of the self-proclaimed Donetsk and Luhansk people's republics were blacklisted earlier so the EU would have to find someone in President Vladimir Putin's entourage.