Bhattacharya's children had been staying with their paternal uncle in Kolkata after being brought back to India following a Norwegian court's order.
"I cannot express myself because it is a huge relief, and I am very happy, the children should stay with me, and I am getting the custody," said Bhattacharya, after the court verdict.
"I was just waiting for the judgement, every time I was just crying and prayed to god- that gives me justice, and I have been fighting for two years. It is really a big dilemma and I can't express myself and now my ordeal has ended," she added.
My children were very maltreated in this family, so the judgement is really perfect because the children were always deprived from the love and care of the mother. And the family discriminated me, and always from the children, so I am getting justice, so I don't say anything about the family because today is a very happy moment in my life. I don't (want) say (about) any kind of dispute in the family or anything," she further said.
The interim order came less than a year after a Norway court sent the children to India on the condition that they would live with their uncle.
Norwegian child welfare services, who had taken away the children and put them in foster care citing "fear of possible violence against the children and lack of adequate parental care", had allowed them to return to India last April after the parents signed an agreement giving the children's custody to their paternal uncle.
The Indian embassy in Oslo had notarised the agreement between the parents, Anurup and Sagarika, and the uncle, Arunabhas Bhattacharya, that the Norwegian court's verdict - that Arunabhas would get custody - would be honoured.
On Thursday, Justice Dipankar Dutta of Calcutta High Court said: "As the mother is the natural guardian, the court is handing over the custody of the children to the mother. Both the parties will submit affidavits and the court will hear the case in March."
The judge added: "The uncle of the children, who had been taking their care since April last, also has the liberty to meet them once in a week. The meeting will take place in the chamber of the mother's lawyer on Saturdays."
Amid a public uproar after a Norwegian court sent the children to a childcare unit, the Indian government had taken up the matter with Norway, where the family had been living for several years.