MOSCOW (Reuters) - President Vladimir Putin signed a law on Friday that bans Americans from adopting Russian children and imposes other sanctions in retaliation for a new U.S. human rights law that he says is poisoning relations.
Washington has called the new Russian law misguided, saying it ties the fate of children to "unrelated political considerations", and analysts say it is likely to deepen a chill in U.S.-Russia relations and harm Putin's image abroad.
Fifty-two children whose adoptions by American parents were underway will now remain in Russia, the Interfax news agency cited Russia's child rights commissioner, Pavel Astakhov, as saying.
The new law, which has also ignited outrage among Russian liberals and child rights' advocates, takes effect on January 1.
The legislation, whose text was issued by the Kremlin, will also outlaw some non-governmental organizations that receive U.S. funding and impose a visa ban and asset freeze on Americans accused of violating the rights of Russians abroad.
Pro-Kremlin lawmakers initially drafted the bill to mirror the U.S. Magnitsky Act, which bars entry to Russians accused of involvement in the death in custody of anti-corruption lawyer Sergei Magnitsky and other alleged rights abuses.
The restrictions on adoptions and non-profit groups were added to the legislation later, going beyond a tit-for-tat move and escalating a dispute with Washington at a time when ties are already strained by issues such as the Syrian crisis.
The adoption ban may further tarnish Putin's international standing at a time when the former KGB officer is under scrutiny over what critics say is a crackdown on dissent since he returned to the Kremlin for a third term in May.
"The law will lead to a sharp drop in the reputation of the Kremlin and of Putin personally abroad, and signal a new phase in relations between the United States and Russia," said Lilia Shevtsova, an expert on Putin with the Carnegie Moscow Centre.
"It is only the first harbinger of a chill."
Putin's spokesman, Dmitry Peskov, said the Magnitsky Act - the U.S. bill which prompted the new Russian law - had "seriously undermined" the "reset", the moniker for the effort U.S. President Barack Obama launched early in his first term to improve relations between the former Cold War foes.
Putin has backed the hawkish response with a mixture of public appeals to patriotism, saying Russia should care for its own children, and with belligerent denunciations of what he says is the U.S. desire to impose its will on the world.
SHARP CRITICISM
Seeking to dampen criticism of the move, Putin also signed a decree ordering an improvement in care for orphans.
Critics of the Russian legislation say Putin has held the welfare of children trapped in a crowded and troubled orphanage system hostage to political maneuvering.
"He signed it after all! He signed one of the most shameful laws in Russian history," a blogger named Yuri Pronko wrote on the popular Russian site LiveJournal.
A hashtag that translates as "Putin eats children" was being widely used on Twitter in Russia on Friday, and pro-Kremlin microbloggers hit back with: "Putin supported orphans".
Russian authorities say the deaths of 19 Russian-born children adopted by American parents in the past decade were one of the main motives for the law as well as what they perceive as the overly lenient treatment of those parents by U.S. courts and law enforcement agencies.
However, critics of the bill say Russian orphanages are woefully overcrowded and that adoptions by Russian families remain modest, with some 7,400 adoptions in 2011 compared with 3,400 adoptions of Russian children by families abroad.
