Two boys kept in Russia by their father in breach of a family court order have been located and returned to their mother in London, lawyers said.
Daniel Neustadt, now eight, and his brother Jonathan Neustadt, now six, have found themselves at the centre of a tug-of-love following the breakdown of their parents' marriage.
Detail of their return was today given to a judge at a hearing in the Family Division of the High Court in London.
Mr Justice Peter Jackson was told by lawyers that the youngsters had been recently found in Moscow after being away from their mother Rachael Neustadt, 36, for about 18 months.
The boys had been visiting their father Ilya Neustadt, 37, in Russia for Christmas in 2012 but he had refused to return them to his former wife - who was their primary carer, the judge had heard.
Ms Neustadt, an American who lives in London, had begun legal action and a judge sitting in the High Court in London had ordered Mr Neustadt, a Russian academic who was a lecturer at the London Metropolitan University, to return the boys to England.
Her lawyers said he had not complied.
She had then asked Russian judges to intervene, using a piece of international law ratified by Russia last year.
And her lawyers said she had won a ''landmark'' court ruling in Russia, when the Moscow City Appeal Court recognised High Court orders made in England.
Her lawyers said the boys had been found at an apartment in Moscow with their paternal grandmother, Irina Mogilevsky.
They said Russian authorities had overseen their collection and handover in accordance with court orders.
Mrs Neustadt, a former teacher from Houston, Texas, said: "I am thrilled and relieved that the boys are back home."
"We have so much to catch up on and so many hugs to make up for."
She added: "I am infinitely grateful to everyone for their help and prayers."
A spokeswoman for law firm Dawson Cornwell, which represents Ms Neustadt, went on: "We are extremely pleased that the Russian authorities' enforcement procedures have now lawfully concluded with the return of the children to England in the most secure and protective way for the children, and in accordance with court orders.
"It is important that England and Russia protect the human and legal rights of children by working together."
Dawson Cornwell originally released details of the dispute in July 2013 after a Deputy High Court judge - who had analysed the dispute at hearings in London - gave Ms Neustadt permission to publicise the case.
The couple also have a third boy, two-year-old Meir, who lives with his mother in London.
Further family court hearings relating to the care of the three children are expected to take place in London in the near future.