MOSCOW — President Vladimir Putin said Thursday that he would sign into law a bill banning the adoption of Russian children by U.S.

citizens, retaliating against a U.S. law that punishes Russians accused of violating human rights and dealing a setback to bilateral relations.

Putin announced his decision at a meeting with senior government officials, including Cabinet members and legislative leaders. The adoption ban, included in a broader law aimed at retaliating against the United States, was approved unanimously by the Federation Council, the upper chamber of Parliament, on Wednesday.

Putin also said he would sign a decree calling for improvements in Russia’s deeply troubled child-welfare system that the Federation Council also adopted Wednesday.

“I intend to sign the law,” Putin said, “as well as a presidential decree changing the procedure of helping orphaned children, children left without parental care, and especially children who are in a disadvantageous situation due to their health problems.”

U.S. officials have strongly criticized the measure and have urged the Russian government not to enmesh orphaned children in politics.

“It is misguided to link the fate of children to unrelated political considerations,” a State Department spokesman, Patrick Ventrell, said Wednesday before Putin announced his decision.

Internally, however, Obama administration officials have been debating how strongly to respond to the adoption ban and are looking at the potential implications for other aspects of the relationship with Russia.

The United States, for example, now relies heavily on overland routes through Russia to ship supplies to military units in Afghanistan and has enlisted Russia’s help in containing Iran’s nuclear program. The former Cold War rivals also have sharp disagreements, notably over the civil war in Syria.

Until Thursday, these larger considerations, along with the possibility that Putin might veto the adoption bill, seemed to forestall a more forceful response from Washington.

The ban is to take effect Tuesday, and some senior officials in Moscow said they expected it to have the immediate effect of blocking the departure of 46 children whose adoptions by U.S. parents were nearly completed. Adoption agency officials in the United States who workregularly with Russian orphanages said they expected the number of families immediately affected by the ban to be far larger, about 200 to 250 who have already identified children they planned to adopt.

Children’s-rights ombudsman Pavel Astakhov petitioned the president Thursday to extend the ban to other countries.

“There is huge money and questionable people involved in the semi-legal schemes of exporting children,” he Tweeted.

Kremlin critics say Astakhov is trying to extend the ban only to get more publicity and win more favors with Putin. A graduate of the KGB law school and a celebrity lawyer, Astakhov was a pro-Putin activist before becoming children’s-rights ombudsman and is now seen as the Kremlin’s voice on adoption issues.

“This is cynicism beyondlimits,” opposition leader Ilya Yashin Tweeted. “The children rights ombudsman is depriving children of a future.”

The bill is retaliation for an American law that calls for sanctions against Russian officials deemed to be humanrights violators.

The U.S. law, called the Magnitsky Act, stems from the case of Sergei Magnitsky, a Russian lawyer who died in jail after being arrested by police officers whom he accused of a $230 million tax fraud. The law prohibits officials allegedly involved in his death from entering the U.S.

Kremlin critics say that means Russian officials who own property in the West and send their children to Western schools would lose access to their assets and families.

Information for this article was contributed by David M. Herszenhorn of The New York Times and by Nataliya Vasilyeva and Mansur Mirovalev of The Associated Press.

Front Section, Pages 6 on 12/28/2012