Ukraine's Deputy Foreign Affairs Minister Olena Zerkal has said expenses for filing the case against Russia in international courts is high, but she said the amounts won in the cases are incomparably higher.

"The cases filed against Russians, which Ukrainian businessman Ihor Kolomoisky, for example, has won cost tens of millions, but hundreds of millions have been won… The same goes for Oschadbank, which won a billion, spending only tens of millions. Yes, we have to spend a lot in order to return this money. Just like Naftogaz is filing suits throughout Europe against Russians in order to return money. But the amounts [it cost to file cases compared to the settlement amounts] are incomparable," Zerkal said in an exclusive interview with the Kyiv-based Interfax-Ukraine news agency.

Zerkal said, "We pay lawyers a lot," and noted the high quality of their work.

"Lawyers in Ukraine cannot even imagine how those lawyers work, I need to tell you. For these two weeks, female assistants had only two or three hours [a day] to sleep, and no one of them complained. They all had smiles on their face and were ready to work, because this is part of their profession – they consciously chose that profession. The same way were those professors with whom we work – they had three to four hours to sleep during that time. They all together with partners prepared own speeches, and then they sat and checked [everything]. The check concerned any word that may potentially be used [by the opposite side] against," she said.