Viktor Vekselberg's assets were frozen by $ 1.5-2 billion

The reason was the US sanctions. To save his money, the oligarch has already met with Russian Prime Minister Dmitry Medvedev.
Origin source
Due to the introduction of US sanctions against businessman Viktor Vekselberg and his company Renova, the company's assets have been frozen from $ 1.5 billion to $ 2 billion, Reuters reports citing two acquaintances with the source's situation.

According to the sources of the agency, it is about blocking dollar bank accounts of companies controlled by Renova. In addition, for a while, the salary accounts of several employees of the Swiss branch of Renova were blocked. After necessary checks, the accounts were again opened.

Renova and Vekselberg hope for help from the Swiss authorities in solving business problems, sources told Reuters, adding that the Swiss government played an important role in the process of withdrawing Sulzer from sanctions.

"European and especially Swiss banks are excessively cautious," said one Reuters source. "Secondary sanctions have a cross-border character and influence countries that are not going to copy American sanctions or even disagree with them," the source added.

As reported by The Bell, referring to sources, Viktor Vekselberg has already met with Prime Minister Dmitry Medvedev and complained to him about the freezing of accounts, the risks of stopping enterprises in Europe, the need to reduce their stake in foreign companies below the controlling stake.

Swiss companies "Renova" Sulzer and Oerlikon because of the sanctions did not pay her dividends for 2017. Thus, the company lost payments totaling about $ 132 million. Sulzer also bought Renova 5 million of its own shares to get out of the sanctions (now the share of Renova in Sulzer was reduced to 48.8%). The money for the sale of shares - $ 568 million - "Renova" will not receive until the removal of its sanctions.