Meriam Ibrahim’s lawyer, Muhannad Mustafa, said she was currently in the U.S. embassy with her family.
Ibrahim had been detained on charges of falsifying ID documents.
She was first released on June 23 when an appeals court lifted her death sentence for renouncing Islam.
Her sentencing in May to hang for apostasy sparked an outcry at home and around the world.
Ibrahim, 27, had been held at a police station in the capital since Tuesday, when she was prevented from leaving the country with her husband, Daniel Wani, and their two children.
Wani is a Christian from South Sudan and is a U.S. citizen.
His wife had reportedly planned to travel to the U.S. with her family.
According to Reuters news agency, quoting her lawyer, Ibrahim was released on the condition that she remains in Sudan.
“Meriam was released after a guarantor was found, but, of course, she would not be able to leave the country,” Mustafa said.
“I would like to thank the Sudanese people and the Sudanese police,” Ibrahim told the BBC in an exclusive interview as she left custody. “I would like to thank those who stood beside me.”
Asked about her plans following her release, she said: “I will leave it to God. I didn’t even have a chance to see my family after I got out of prison.”
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