Iranian officials have told a British woman jailed on unspecified security charges to take her 2-year-old daughter to prison with her or give up custody.

Nazanin Zaghari-Ratcliffe, 37, a charity worker with dual British-Iranian citizenship, was sentenced to five years in jail on “national security charges” in September, one of three Britons being held by Tehran. Amnesty International reported Thursday her health has suffered since she was incarcerated.

Zaghari-Ratcliffe, whom Amnesty has designated a prisoner of conscience, is being held in Evin Prison, which has no suitable facilities for children.

“What kind of refined cruelty is it that would involve presenting a mother with a ‘choice’ to either jail her own daughter or give her up entirely?” asked Kathy Voss, Amnesty U.K.’s individuals at risk campaign manager.

Zaghari-Ratcliffe was arrested April 3 at Tehran Airport with her daughter, Gabriella, as they prepared to return to Hempstead, England, following a brief family visit.

Zaghari-Ratcliffe’s husband, Richard Ratcliffe, told the Evening Standard the British Foreign Office is not doing enough to free his wife. He said he had planned to travel to Iran to pick up his daughter but Zaghari-Ratcliffe begged him not to take her away.

“I still want them home for Christmas,” he said. “But we will see what happens next on Jan. 4,” the date her case comes up for appeal.

Demonstrators caroled outside No. 10 Downing St. Monday to urge the government to take action.

“Nazanin is one of the bravest people I know but she’s at breaking point. She’s been separated from me and our daughter — completely illegally — for no reason and with no charge,” Ratcliffe said last week. "We are an ordinary family, like millions of others. And it’s just unimaginable that my wife is in prison, and won’t be with either me, or her own child at Christmas. I urge the British government to bring all their weight in the world to bear and get my wife out of jail before it’s too late.”

Zaghari-Ratcliffe is seen as a bargaining chip in Iran’s efforts to pressure the British government to turn over hundreds of millions of pounds Tehran claims it is owed. Iran is holding two other British hostages, Kamal Foroughi, 77, an oil and gas consultant serving an eight-year sentence for espionage, and Roya Saberi, 49, who was jailed for 20 years for criticizing the Iranian government on Facebook.