The Russian gas transit to Europe across Ukraine is a complex matter, and for solving it one should do more than just talk about it, advisor to President-elect Volodymyr Zelensky and ex-Ukrainian Finance Minister Oleksandr Danyliuk has said.

"It is still too early to talk about this. We understand that there is a big risk of losing [Russian gas] transit. Now we need not to talk, but to do more," he told reporters when asked about entering into an agreement on gas transit at meetings of Zelensky's team members with European diplomats and diplomatic advisers to EU leaders.

"This is a difficult issue. Much depends here on the position of the United States, the position on Nord Stream 2. This is a rather complex matter that you need to find a solution for," said.

He also said that on Thursday during a conference on energy security in Brussels export of liquefied natural gas from the United States to the EU was discussed.

"We met with the U.S. side, discussed the issue of Ukraine's energy security, the challenges that we face this year in the near future. We were looking for possible solutions. Our delegation had meetings at a high level," Danyliuk said.