Russia's president on Friday signed a new law that will break the hearts of some Bay Area families and others nationwide awaiting the arrival of orphaned Russian children they have met and chosen to adopt.

In a brusque move aimed at rebuking American foreign policy, President Vladimir Putin approved an immediate U.S. adoption ban. The Russian parliament had approved the measure Wednesday."Everybody's devastated," said Janet Shirley of Bay Area Adoption Services in Mountain View on Thursday when Putin's likely action was in the news.

Among those petitioning to stop the ban is 18-year-old Anastasia Helberg, whose life brightened when she moved to California from a crowded Russian orphanage seven years ago.

Putin "is not thinking about these kids," she said. "It's really sad that these kids are stuck there and have no chance to come over here and live a normal life with a family."

American families have welcomed more than 60,000 Russian children into their homes since 1992, including nearly 1,000 last year, but an escalating diplomatic dispute threatened a sudden end to the exchange.

The ban could halt the adoption of 46 children already matched with American families and also affect up to 1,500 families in some stage of adopting, said Lauren Koch of the National Council For Adoption.

About 740,000 Russian children live without their parents, most of them in state-run institutions, according to the United Nations Children's Fund, which on Thursday urged the Russian government to "let the best interests of children" determine its policies.

One California family working with a Pleasant Hill adoption service is in Russia now with a newly adopted child, hoping to fly out before the ban takes effect. Two other families have bonded with their children and are waiting for a hearing in Russian adoption courts, so the children are not yet legally theirs.

Several other Bay Area families are in some stage of adopting but declined to speak publicly, fearing that the exposure could damage their chances.

The Russian bill calls for the ban to take effect Tuesday, though adoption agencies had hoped Putin abides by a November agreement between the United States and Russia that requires a year's notice.

"At a very minimum," Koch said, he should "at least let those 46 children come home with their families."

Russian lawmakers are using the ban to retaliate against new American travel and financial sanctions targeting Russians accused of human rights violations. The controversy also reflects deeper Russian concerns about losing children to foreigners, especially amid several well publicized cases of American abuse and neglect.

Russia was the third most popular country for U.S. adoptions in 2011 after China and Ethiopia, despite an increasingly laborious and costly process that requires prospective American parents to visit the country three times to bond with the child, attend a court hearing and undergo a battery of background checks.

"Russian adoptions are probably -- on a scale of zero to 10 -- they're 9.5 in difficulty," Shirley said. "Parents who adopt from Russia are very dedicated."

Some white couples or Russian-Americans look to the country for children who share their fair complexion or cultural ties; single mothers choose to adopt there because Russia, unlike many countries, doesn't require married parents; and parents desiring to adopt children as young as 12 months also find more options in Russia, adoption coordinators said.

Amid domestic protests over the proposed ban, Russian leaders promised this week to improve the lives of abandoned Russian children and those with medical conditions so that they don't have to leave. Legislators have pledged to clean up the nation's shabby patchwork of more than 2,000 orphanages and encourage more domestic adoptions and foster care. Those who have found homes with loving American families remain skeptical.

Now a high school senior living with her adoptive parents in Lafayette, Helberg grew up bunking with other orphaned girls in the rust-belt Russian city of Yoshkar-Ola some 500 miles east of Moscow.

Many abandoned children who aged out of her orphanage fell into street crime or prostitution, she said.

"I know that I would have not been in a good place if I were still in Russia," she said. "I would not have the things I have today. No family, and no money."

The Russian consulate in San Francisco declined to discuss the proposed ban before Putin signed it Friday "because it hasn't been passed yet," said consular spokesman Yevgeny Avdoshian. "We don't comment on the work of the legislative branch."

U.S. diplomats, however, voiced "deep concerns" over the Russian government's maneuvers.