In the wake of the downing of Flight MH17, U.S. lawmakers are considering slapping further sanctions on Russia.
Senator Chris Murphy, chairman of the Senate's Europe subcommittee, says he plans to reach out to key senators this weekend to discuss "essential new sanctions legislation."
Murphy said if President Obama were to take more aggressive action against Russia, it would be useful for him to have lawmakers' full backing.
Murphy added it would be especially helpful if European nations joined in.
The European Union has been more reluctant than Washington to impose sanctions on Moscow, due to its close economic ties with Russia.