U.S. President Joe Biden will join allies in applying additional sanctions against Russia and tightening existing ones during his trip to Brussels this week, U.S. National Security Adviser Jake Sullivan told reporters on Tuesday.

Biden intends to announce sanctions on more than 300 members of the Russian State Duma as soon as Thursday during his trip to Europe, the Wall Street Journal reported Tuesday, citing U.S. officials and internal documents.

Biden will travel with U.S. Defense Secretary Lloyd Austin to Brussels, where NATO and the European Union are based, on Wednesday for meetings on Thursday with fellow leaders. Then he plans to travel to Warsaw in a show of support for an ally that shares a border with Ukraine.

(With input from Reuters)