MOSCOW (Reuters) - Russia's upper parliament house unanimously approved a bill on Wednesday that would ban Americans from adopting Russian children, in retaliation for a U.S. law that punishes Russians accused of human rights violations.

The bill, which President Vladimir Putin has hinted he will sign, would also outlaw some U.S.-funded non-governmental organizations and impose visa bans and asset freezes on Americans accused of violating the rights of Russian citizens.

It is Russia's response to the Magnitsky Act, a law signed by U.S. President Barack Obama earlier this month to bar Russians accused of human rights violations from entering the United States and to freeze any assets they hold there.

The Federation Council, Russia's upper parliament house, voted 143-0 to approve the bill, which has drawn condemnation from rights activists and Kremlin opponents who say lawmakers are playing a political game with the lives of children.

Putin has signaled support for the measure despite unusual criticism from some government officials, including Foreign Minister Sergei Lavrov and a deputy prime minister who has warned Putin that it could violate international agreements.

The U.S. law and the Russian response are adding tension to the relationship between the countries, which is already strained over issues ranging from Syria to Putin's treatment of opponents and restrictions imposed on non-governmental organizations since he began a new term in May.

(Reporting by Alissa de Carbonnel; Writing by Steve Gutterman; Editing by Pravin Char)